I've never played Lemmings 3D myself, once this project is playable, it may be my first chance to play the game.
Um, this is just a level editor though, not a level player. You still need Lemmings 3D to actually play levels. You can probably find a copy of that anyway on the Internet, you don't need to wait for a completed editor to play the official Lemmings 3D levels. 
If the version you acquire has the terrain on Tricky 10, Tricky 14, Tricky 20 and Mayhem 5 blacked out, let us know. Many abandonware sites have copies with a corrupted TEXTURE.000 file (only used by these four levels); simply replacing it with a good copy resolves the issue, and we can easily provide that.
You'll also need DOSBox to play it. If the copy you "acquire" is the CD version, note that the CD version will refuse to run unless (it thinks) a CD drive exists. This is weird, because it doesn't actually care whether the Lemmings 3D disc is in the drive (or even if any disc is at all), just that a CD drive exists. The floppy version does not have this issue, but cannot play CD audio (it can, however, play the CD animations, if you copy them across from a CD copy).
You'll probably need to get the PC version working one way or another if you want to make or play custom levels - if the editor works as-is with the Playstation and/or Saturn versions, cool, but at this point I have zero intention of specifically
trying to make it compatible (my first priority is getting it working 100% with the full version of L3D, and then after that the demos and Winterland - and once that's done, chances are my next focus will be making some levels). At the very least, it'll probably require a copy of the graphic files from the PC version. If you just want to play the original game though, the Playstation version may be the easiest way to do this.