Okay, good thing I waited with an update until version 12.10 was released, because a bunch of my old replays broke for unknown reasons.
Maybe this has to do with yet another physics change? I remember reading something about a Miner-Basher inconsistency being changed?
It's not mentioned in the 12.10 changelog though, and I can't seem to find a Bug Thread for it either.
Another thing is that lemmings now seem to slip through ceilings through which they didn't use to slip before. (Since lemmings can slip through thin stripes of terrain, they also do that at the top level border, because terrain above the level border is treated as non-existent, even if a thicker terrain piece is placed there.) I had fixed the ceilings for all levels for which it was relevant during the initial New-Formats conversion, so I knew about this. However, now there seem to be levels affected that weren't before.
Those are easy enough to fix: Just add a couple of pixels extra to the Y dimension of the level, select everything, move it down that number of pixels, and the steel piece or whatever I've placed at the ceiling to prevent lemmings from walking upwards and dying gets lowered further into the level. It takes a while to identify them all, though, especially since I've fixed them all before.
A similar thing is true for the Glider-Faller physics change: I had fixed all levels where this was relevant, but now it's suddenly an issue again.
The strangest error was on the level "Streets of London",
where somehow the save requirement had been raised from 57 to 59 (out of 60), breaking my solution because I had used two of the three Bombers.
I also had to correct the object name for nin10doadict's cat trap again in one level file ("The lion sleeps tonight"), changing it from the style "nin10_cattrap" to "nin10_misc", and changing the object reference to "TrapCat" instead of "catTrap" - even though I was certain I had already done so.
My replays are sorted and the solved vs. unsolved levels after the Mass-Replay check are easy enough to tell apart;
I'm just referring to finding out whether the level broke because of a ceiling death, the Glider-Faller physics change, or because of some other reason.
So far I've fixed everything from Noisemaker up to the end of Professional, but there are still many unticked levels left.Sometimes, there's actually nothing wrong with the solution, and the reason the level remains unticked is probably just because the level counts as "undetermined", taking longer than the cutoff amount of time after the last skill assignment for everyone to get to the exit. In that cases, I just run the same replay over the level again that didn't pass the mass replay check (and left the level unticked in the selection menu), and it passes as normal and the level gets ticked. So it is also not a problem of the levels not having my correct user name, because I've run them all through the Replay Refresher again.
At least the menu signs were easy to reset to my custom ones . Lemmings World Tour actually didn't have a custom rank sign before (custom rank labels, yes, of course, but not the sign itself). Fortunately, I could still grab those PNGs from Old Formats.
I just had to add separate image files for the old up and down arrows. The new ones look nice on the black menu signs I had made for Lemmings Open Air, but I want to keep Lemmings World Tour as it is.
TL;DR: A bunch of levels broke in version 12.10 and this is clearly more than I can fix in one afternoon. This pack is currently not ready to be played in version 12.10! If you're currently playing it, either keep it in version 12.9 or wait until the update. Either way, be prepared for a bunch of your replays breaking when you update to 12.10.
As a result, I'm also not sure to what extent IchoTolot's and kaywhyn's remaining replays will still work if I watch them now in version 12.10...I expected some levels breaking with the update, but certainly not THAT many at once!