The Lemmix editor doesn't have sound.
Sound has always been there in the editor's playtest mode, you just have to set it up yourself.̆ It is true though that there's no music there (at least not yet).
If the DOS clone has stuff like save states, fast forward, jump ten seconds etc. there's no reason there shouldn't be easier passwords, since you can't really argue that its trying to replicate the original experience.
That's somewhat true.̆ Fast forward though is already available in certain official versions of Lemmings such as Window's.̆ Save states falls under the umbrella of action-replay and that too is available in versions such as Window's, although I'd have to argue too that I'd rather only allow replay and not savestates for the clone, even if the rest (savestates, etc.) are really just enhancements on replays.
In contrast, I find it a bit of a stretch to see cheats as an "improvement" or "enhancement" on levelcodes.̆ If you are going to make cheats the default in the player, you might as well remove the levelcode interface altogether since it'd be a moot point.̆ I personally would like something like the level selector in the editor if I want to jump to particular levels (because, I don't know about you, but
I would still need to look up the level number if I want to go to a particular level!).
That being said, I do understand that pragmatically, everyone who cares has probably already played the levels already and could do away with the levelcodes.̆ I will also share that the few occasion I played the Windows version, one frustration I have is that in that version, they don't even have passwords--they keep track of your actual progress via files, and their system don't even let you jump to random levels via password--you'd have to "skip" the preceding levels one by one until you reach the level you want.
One possible compromise is a "activate cheat" levelcode, which actually exists in the original DOS game too.̆ I think it's "BILLANDTED" or something.̆ Even in the original game, activating cheat mode merely allows you to "win" any level by pressing I think Alt+F5 or something while playing that level (somewhat like the "skip this level" feature in Windows Lemmings).̆ But for the clone, perhaps we can have levelcode "ERICLANG" activate a cheat mode that allows the "MAYHEM30" cheat codes.