Steps to reproduce this bug:
1) Start a level with a hatch, that has preassigned skills.
2) Observe that the lemmings have the correct permanant skills assigned to them, when they drop out of the hatch.
3) Optional: Do some terrain modification, like digging or bashing somwhere
4) Open the in-game level selection menu (usually F2) and press "Cancel" to continue the current game
5) Optional: First notice that your terrain modifications are gone.
6) Then notice that the lemmings spawning now do no longer have the preassigned skills. Alternatively it may rarely happen that all objects turn invisible and that the lemmings now spawn as swimming-floating-gliding zombies.
7) If you use some backwards frame-steps, your terrain modifications will reappear (as the save-states do have the correct information)
8) But even if you framestep back to the beginning of the level, the preassignments never reappear.

Exiting the level and starting it new fixes all the problems.

WARNING: This is still an experimental version and any of the shimmier physics may still change! Do not complain if they break the levels, you create with this version.

After the usual warning, here is the good news: This experimental version allows you to test the shimmiers. It should not crash every ten seconds and shimmiers might even somewhat behave like you would expect them to.

Installation:
Although the stable version should have no problems with the modified graphics for the shimmiers, I still recommend starting with a new installation of the stable NeoLemmix version (or a copy of your current one). Then extract the attached zip file in the folder, replacing the older files with the ones in the zip file.

How can I create levels with shimmiers?
The zip file also contains a new version of the editor, that supports shimmiers. Alternatively open the nxlv file and add among the other skills a line like "SHIMMIER 20".

What should I look for in this experimental version?
1) Crashes: I might have overlooked some places, that have to be adapted to the existance of a new skill.
2) And equally important: Anything that didn't feel right or suprised you. I would like the shimmiers to be as intuitive as possible, and we are now in the unique situation, that there are a lot of players with a fresh mind and without preconditioning by previous shimmier versions. So please report anything that caused a raised eyebrow.
3) Whether the animation looks good. For the shimmier itself I used Raymanni's sprites, so I am less worried there. But the reacher animation might very well be something that can (and should?) be improved upon. As I mentioned frequently, I am not really good at creating sprites, so if you can improve the sprites yourself and post the new ones here, it would be much appreciated. (But even comments like "Frame 5 of the reacher animation looks out of place" do help).

What is left on the ToDo-list?
- Hunting for glitches (though this will have to wait until the main physics rules have stabilized)
- Adapt the pickup-skill sprites for non-default graphic sets. Currently you can only use shimmier pickups, if the graphic set uses the default pickup sprites.
- Add support for shimmier talismans. The player should already be able to handle them correctly (though I haven't tested it yet), but the pack toolkit doesn't allow creating such talismans. 
- Fix all the issues you will find.

Gronkling wishes that some of "his" styles should not be credited to him, because they are actually not his. The styles are currently named:
gronkling_angelisland
gronkling_chaosangel
gronkling_cybertrack
gronkling_technobase
I am happy to rename them to "sonic_[whatever]", however we have a backwards compatibility problem here: Everyone having used some of the pieces in these styles in their level will have to run a text-replace over their level file, to let it point to the renamed style.
It will probably only concern a very few level designers, because the styles are pretty new and as far as I can tell, not too popular at the moment. However I might be completely mistaken. So I would like to know:
Have you used any of these styles in your levels? If so, are you fine with running a text replace over them?

Sometimes the location zoomed into does not coincide with the cursor location, when using the mouse wheel. I tried fixes in the previous editor versions 1.8-1.10, but it still doesn't work.

PS: This post is basically just a reminder for me to fix this.

I am not suggesting here to go back to the L1 order and add the new skills at the end!

The current order is:
Walker, Climber, Swimmer, Floater, Glider, Disarmer, Bomber, Stoner, Blocker, Platformer, Builder, Stacker, Basher, Fencer, Miner, Digger, Cloner

My suggestion would be:
Climber, Floater, Glider, Swimmer, Disarmer, Blocker, Bomber, Stoner, Platformer, Builder, Stacker, Basher, Miner, Digger, Fencer, Walker, Cloner

Here are the reasons:
1) The walker skill is not a permanent skill, so should not be grouped with them. Actually if there is any other similar skill, then it would be the cloner, because they are non-permanent skills not modifying any terrain (with the blocker being the only other one).
2) Climbers, floaters and gliders share one similarity, namely they deal with high walls (just going on opposite directions). On the other hand swimmers and disarmers are similar, because both deal with previously deadly objects. So I would like to move the swimmer after floaters and gliders.
3) I would like to have blockers and bombers next to each other, because quite often they are used on one and the same lemming. On the other hand grouping bombers and stoners as the lemming-killing skills makes sense, too. So I suggest to move the blocker in front of the bomber.
This has the additional advantage that the blocker (which is usually applied first) now comes before the bomber (something I never understood about the L1 oder).
4) In my opinion there is no intuitive order of the four terrain removal skills (apart from the bomber). So I would suggest moving the fencer after the digger, to keep the "basher-miner-digger" oder that we are all used to.

A much more radical suggestion would be:
Climber, Floater, Glider, Swimmer, Disarmer, Platformer, Builder, Stacker, Stoner, Basher, Miner, Digger, Fencer, Bomber, Blocker, Walker, Cloner

Again the list of reasons (in addition to the ones above):
1) This groups the skills as "permanent", "terrain adding", "terrain removing", "lemming-only"
2) However it splits up the two lemming-killing skills, which might be a downside.

PS: This suggestion was triggered by the suggestion to reorder the skills in the editor, because I don't want to reorder them twice.

Currently we tag our lemmings level packs with the platform name [Lix] or [NeoLemmix], they are created for. However with the change from the old-formats NeoLemmix to the new-formats one with their incompatible pack structure, this creates questions:
- How do we distinguish packs made for the old formats NeoLemmix from the ones made with the new formats version?
- How can a user, who has only one of the NeoLemmix versions, see what level packs are available for them?

My suggestion would be to split this board into three subboards, one for Lix, one for old-formats NeoLemmix and one for new-formats NeoLemmix. Packs for Lemmini or vanilla Lemmix may stay in the main board.

Do you think the questions above are actual problems, or is this just a pet peeve of mine? Would such a split help you to find the packs you want to play? Do you have better suggestions?

If one flips a receiver, where the corresponding nxmo file does not specify the trigger width to be 1, then the trigger area is one pixel too far right. This will be fixed from version 12.0.2 on.

After about 5 months of testing, I think the new-formats version of NeoLemmix is ready to be released as a stable player.

If you not yet have a new-formats player, then please download the attached installer (version 1.1), make sure you have internet connection and run the installer. It will download the main game (in the version available on the NeoLemmix homepage), editor and styles together with a few example level packs.
Alternatively you can download the same stuff directly here:
- The player, editor, ...: https://www.dropbox.com/s/p9a6iewz4841039/NeoLemmix_Full_2018-10-21.zip?dl=1
- All the new styles: https://www.dropbox.com/s/rzea4tapto1kr72/styles_2018-10-21.zip?dl=1
This contains NeoLemmix V12.4, the Editor V1.11, the Pack Toolit V1.6 and the GraphicsTool V1.3. It no longer contains the conversion tools for old styles and level packs. If you need them, they are still available on the NeoLemmix homepage.

There are still some missing features and originally I wanted to implement at least some of them before the first stable release, but sometimes there is a slighty difference between wish and reality. The main ones are:
1) No automatic download of missing graphic styles, but you have an installer instead, that automatically download them.
2) No shimmier and no jumper skill yet.
3) No exits with resticted number of lemmings allowed to enter.
4) No terrain piece grouping for level creators.

EDIT 2018-10-21: The links in this first post now point to the latest version again.

NeoLemmix is a clone of the game Lemmings by DMA, that greatly enhances the playing experience:
- New skills like the platformer, glider or fencer
- New interactive objects like teleporters, pick-up skills and locked exits
- Dozens of new graphic styles that carry you off into the deep sea, a world of horrors or even a beehive...
- Features that will help you place your skills correctly like blueprints for builders or miners, or that help you rectifying mistakes like replaying the previous attempt or backwards time skips
- ...and a level editor that allows you to create your own challenges!

Where can I get NeoLemmix?
Just download the attached installer, make sure you have a working internet connection and run it. It will download and install NeoLemmix. You should download at least the game, the styles, and at least one level pack. Alternatively you can always find the up-to-date version on the NeoLemmix homepage.

Note that the list of level packs provided by the installer is not a complete list of all available level packs. You can find others on the forums.

NeoLemmix doesn't work for me! What can I do?
Either post your problem here on the Lemmings forums or visit the IRC channel #neolemmix.
Note that NeoLemmix is currently only available for Windows, but not for Linux or Mac.

What levels should I play first?
We have lot of high-quality level packs here, starting from very moderate difficulty to incredibly insane ones.
If you are a fan of the original levels, then check out Lemmings Redux, which is a best-of selection among the official levels. (This pack is included alongside newer versions of NeoLemmix.)
If you want to start on custom levels, we can recommend IchoTolot's Lemmings Reunion, which has a very nice difficulty curve.

I have made new levels or a new graphic style. How can I make them accessible to the public?
We all love to see your content! Feel free to post your levels in our Level Packs board, and your graphic styles in our NeoLemmix Graphic Sets board.

I would like to chat about NeoLemmix, Lemmings in general or any other topic...
Then visit our IRC channel #neolemmix. Usually it's most active around 7pm to 3am UTC (i.e. afternoon in the US and around midnight in Europe). There is also the channel #lix, for those who want to discuss Simon's competitor for NeoLemmix

I would like to contribute to the NeoLemmix code! How can I do so?
All parts of NeoLemmix are open-source. The following links point to their git repositories:
1) Player code (written in Delphi)
2) Editor code (written in C#)
3) Installer code (written in Delphi 10.3)

Deprecated tools
4) Pack Toolkit Code (written in C#)
5) Graphic Style Tool Code (written in C#)

EDIT by namida, 2019-08-17: Replaced Nepster's installer with a new, open-source one.
EDIT by namida, 2020-02-16: Uploaded installer V1.1.

Assume the following situation happens in a thread: The first post has the title "Beginning", while for the second post the author has changed the title to "No longer a beginning". Then I want to reply to it and write the third post.
Expected behavior: My third post has the title "No longer a beginning" (unless I change the title again)
Actual behavior: The third post has the title "Beginning".

As usually the latest title describes the current discussion topic better that the original first title, I suggest changing this behavior. As Flopsy mentioned in chat, the current behavior is especially annoying when having a thread for multiple graphic styles: Every time a new style gets added, one has to modify the very first post instead of simply posting a new post with an adapted title.

Whenever I want to download an attachment, I have to try that twice: After the first click I always get the error "The requested URL /index.php was not found on this server." The second try then works fine.

Quote<GigaLem> Well Until I can get someone who can perfectly port to the new format, I'm not upgrading

I know that your levels using the Freedom planet styles need a lot of work. I can totally understand if you don't want to do this yourself, especially as I am the reason for this high workload (with me merging lots of pieces). So if you would like to have new-formats versions of your levels, you can send them to me and I will convert them. I will even fix the ceiling issues.
The only changes you really have to make yourself is fixing levels that currently use radiation or slowfreeze objects.

Quote<GigaLem> is the Starport set available in new format yet?

Yes, it is. I have converted all of your Freedom Planet styles.

Quote<GigaLem> also, you'll need to get the entrances back into the dreadnought set because, they're needed for it
<GigaLem> I'm too affraid to talk to nepster about the dreadnought entrances, because im expecting a big "NO"

I checked again today, but the "gigalem_dread.dat" file does not contain any hatches. If you send me the hatch sprite, I will add it to the "gigalem_dread" style with the next update.
And I never removed anything that cannot easily remade with the remaining pieces, mostly be rotating/flipping the still existing piece correctly.

Quote<GigaLem> I feel like nepster's making the update for him and only him sometimes, and it just ticks me off

If I did that, I would not have asked anyone for their opinions on the forums, and I would have removed backgrounds, disarmers, splat-pads and a lot of other stuff, which I personally don't like but that is still rather simple for new players to understand. And please don't confuse "many posts with one opinion" with "many people having one opinion": We have some very vocal members here (including me sometimes), but I try to balance the opinions of everyone, even if they only posted once.

Finally: If you have problems with anything I do, then please tell me! I might say "no", I might not agree with your point and I might decide against you, but I want to hear your opinion! Ranting in chat, especially when I am not there at that time, doesn't solve any issues!

Internally the lemming location is one pixel below the lemming's feet. Most of the time, this is only important for the programmer modifying the code and not the player. But there is one exception: Trigger areas in the clear-physics mode.
For new players it might be much easier to understand if the lemming's position would be directly at the lemming's feet, i.e. when the lemming triggers the object if (and only if) it's feet hit actually the trigger area.

I will certainly not change all the code internally, but I can change the display of the trigger areas in clear-physics mode (and as well in the editor and the graphics tool) so that the trigger areas are always displayed one pixel higher than they are at the moment.

How would you feel about this change? Do you think this is sensible, or do you rather prefer to keep the current situation to avoid confusion?

Given the frustration several members of this community voice regarding the removal of several features, I feel the need to present my philosophy about where NeoLemmix should head to.

My main guideline is: How does a change affect the user, who plays a level or a pack?
The reason for my decision to focus on players, not on level designers is actually very simple: Every single level is created by only a single user, but played by a lot of others.

This has a few consequences:
1) All rules should be easily discoverable and if one knows the behavior in similar situations, the player should be able to correctly guess the behavior in the current situation.
2) Ideally all levels should be playable without any of the helps that NeoLemmix offers. The helping features like clear-physics or frame-stepping should never be necessary.
3) All player styles should be viable, be it that they test a lot of things explicitely or be it trying to solve the level in the head first.
4) Already existing levels are unimportant: If a level does not use player-confusing features, then it will automatically work in the future, too. If it relies on edge-cases that change now, then it either can be saved by small changes or it's not a big loss. This is a very harsh point of view, but actually based on two reasons:
- Removing some levels (be it because they don't fit the current culture or have become impossible) is an absolutely normal procedure. This has happened when moving from Lemmix to NeoLemmix, and even at various points during the existing NeoLemmix development (not only due to the removal of gimmicks, but at a lot of other updates, too), and it will continue to happen in the future.
- The given feedback to level packs has (at least up to now) definitely favored levels that use the behavior players expect and know, but do so in interesting, unexpected or new ways. On the other hand levels relying too much on the fine points of the game mechanics or the terrain layout usually generate not quite as enthusiasthic feedback.
5) The amount of code necessary for a feature is absolutely unimportant: If a useful feature needs a lot of code (but is still managable for me), then it will be added. If a feature only needs a single line of code, then that doesn't mean that it should be added or be kept.

Raymanni produced new platformer and stacker animations. Huge thanks
   

I love the new stacker animation and would like to replace the current default one with this one. Anyone who disagrees?

But the new platformer sprite doesn't fully convince me. The lemming movement seems a bit weird. Opinions?

Usual lemmings can survive a 63 pixel fall. But if they have been blockers and the earth below their feet is removed, then they suddenly splat already after 60 pixels.

Example level is attached.

Currently teleporters may turn lemmings around when entering them. More precisely (I think) it works as follows:
- If the teleporter object is set to "Face Left", then all lemmings will be turned around when entering the teleporter.
- If the receiver object is set to "Face Left", this this doesn't influence lemmings at all.
- If teleporter or receiver objects are set to "Flip", then this just mirrors the sprite, but doesn't influence the game physics.

I always found this extremely confusing, both as a level designer and as a player. Actually I only understood this behavior after creating several test levels featuring the various combinations. And as a player I still always expect the lemmings to keep their direction and am rather surpised if I encounter one of the rare levels that uses teleporters turning the lemmings.
In addition the usual teleporters are far more used than the lemming-turning ones. So I suggest removing lemming-turning teleporters completely from NeoLemmix.

A few weeks ago I stumbled over the website Clickmazes, which has some brilliant logical puzzles (and several actual mazes). Unfortunately most of them use in-browser Java applets, which are a nightmare to run in any modern browser. I would still encourage you to have a look at it, if you like logical puzzles.

One of these puzzles is the BoxPuzzle, which is the hardest logical puzzle type I know that fits on a 3x4 grid. Given the problems in playing the puzzle on the homepage, I coded it myself and created 25 new puzzles for it (to avoid too heavy copyright infringements). This game is attached to this post as a Windows application.
Linux users can find the C# code in my git repo and build from there.

There seem to be several different opinions floating around about how the grid should work. I have no preference in any way, because I am not using it, but I prefer not always having someone complaining whenever I make a change.

So my questions are:
- How should the grid work when you drag pieces around?
- How should the grid work when moving pieces with the keys?
- How should the grid work when duplicating a piece?
- How should the grid work when inserting a piece previously copied to the clipboard?

Download links:
Everything except styles: https://www.dropbox.com/s/5qxxmtdr10t71uk/NeoLemmix_Full_2017-11-28.zip?dl=1
Styles: https://www.dropbox.com/s/hklgf36wqqtfmju/styles_2017-11-28.zip?dl=1
NeoLemmix player: http://www.neolemmix.com/download.php?program=16&exp=1
Editor: http://www.neolemmix.com/download.php?program=17&exp=1
Pack Toolkit: http://www.neolemmix.com/download.php?program=18&exp=1
Graphic Set Tool: http://www.neolemmix.com/download.php?program=19&exp=1
Pack Converter: http://www.neolemmix.com/download.php?program=46
Graphic Style Converter: http://www.neolemmix.com/download.php?program=45

Components:
1) NeoLemmix player (version 11.15.24): The new-formats player. It can be used from now on, as the file formats are stable starting with this version. It is fully functional, except for the online options (and of course any bugs it might have certainly has). New features include:
- namida's level selection menu, that allows jumping between packs.
- Options and hotkeys can be changed on every page, even when playing a level. Press F3 for this.
- The level selection menu is available from every page, too. Press F2 for this.
- Hatch markers to show preassigned skills. The same appear when moving the cursor over zombies, or in clear-physics mode when moving over a usual lemming.
- Radiation, Slowfreeze and anti-splat pads removed from the game.
- Time limits are now displayed in red, instead of the usual green.
- Updated options menu with far less hardly used options.
- The hotkey for the talisman menu is now F4, no longer F6.
2) Various helper files: The new-formats version reads a lot of info from external files, which are included as well.
3) NL Editor (version 1.5): A new editor for new-formats NeoLemmix levels.
4) Pack Toolkit (version 1.2): A tool to create and modify level packs for the new-formats version. It offers not yet all the options the player supports, so if you are missing something, please tell me.
5) Graphic Style Tool (version 1.0): A tool to create and modify graphic styles in the new-formats version.
6) Pack Converter: A tool to convert your old level packs automatically and (almost) completely to the new-formats version. Please see the next post for more details.
7) Graphic Style Converter: A tool to convert your old graphic styles to the new-formats. For details, please see the conversion topic.

Installation:
- Create a completely new directory and extract the file "NeoLemmix.zip" from the first download link into this new directory.
- Extract the file "styles.zip" into the same folder. You should now find a subfolder called "styles" containing all currently available graphic styles for the new-formats. Warning: Due to the large number of files, extracting this zip file may take a while.

Further advise:
- If you want to retain your options from V11.13.XX, copy the file "NeoLemmix147Settings.ini" into the same folder, where the new NeoLemmix.exe is located. This has to be done before starting the NeoLemmix.exe for the first time!. If you then start NeoLemmix with this file present, then it will read the options from this file, and save it in the subfolder "settings". Afterwards you can again delete the file "NeoLemmix147Settings.ini".
- If you want to retain your hotkeys, do the same but with the file "NeoLemmixHotkeys.ini".
- I do not guarantee that previous new-formats versions (up to any version 11.14.19) will work correctly or are compatible in any way with any of the other tools. There have been a few slight changes to the file formats in the meantime.
- I strongly encourage to delete any previously downloaded new-formats styles. Even the styles you got from the general download in the graphic set conversion topic contained a few bugs, that I fixed now!