For those who don't know what I'm talking about, you can simply ignore this post.
For the others - especially given that NL no longer requires downloading the styles seperately from the game itself, there is little purpose to the installer anymore. Yes, it's convenient for packs, but this relies on me manually updating links, which in turn generally relied on people informing me when the links change - which very few people actually bothered to do (or perhaps, did not realise that eg. if you replace an attachment on a post, the new file has a new link).
I have unstickied the installer a long time ago now, and to be honest I'm not sure how people are still finding it. I have still been receiving occasional requests to add / update packs in it, so I'm making this post to make two things clear to everyone - firstly, that said list is no longer being updated, and secondly, that the installer may stop working altogether at any time.
To download NeoLemmix itself, download the ZIP and extract. The editor is a single EXE file that should go in the same folder as NeoLemmix. You can use the in-game style manager for any styles you want (or else, the all-styles ZIP is still available for those who prefer it - though do keep in mind it may be slightly out-of-date compared to the style manager, usually only by a couple of weeks at most). As for packs, that does have to be done manually - but if creators are following recommendations, the ZIP file will also be set up so you can extract it directly to your NL base directory.
I might look at reviving the installer in some form once NL reaches a final version, or at least very close to it - likely without the pack downloading feature for the most part, though possibly with an option as to whether or not Redux and/or Intro Pack are downloaded. (I could also include Lemmings Plus without the technical issues, but I feel that would be giving special status to my own packs without good reason, whereas Redux and Intro can be justified as special cases.)
(Yes, it does pick up the newer versions of NL itself - this is because when it connects to the server to check what downloads are available, the server is configured to always give it the newest NL version, not a specific exact version.)