Sorry, I'm still struggling to find my way around this music editing thing 
I think this is an IT of the piece. I haven't worked out how to make it loop correctly.
I'm not sure I did it correctly either (it is surprisingly hard to test this other than just actually trying it out via NeoLemmix or whatever game engine this music is destined for, which I'm not ready to set up at the moment), but try this and see if it works better. The looping is not carefully set, I just set it to loop back to beginning when it reaches the very end, assuming it works.
The thing that makes it so hard to test is that, it looks like a lot of media players tend to ignore any built-in looping in MOD-type files, probably because most of the time you want to play the music as part of a playlist, and thus wouldn't want any built-in looping to hijack the playlist and prevent the player from moving into other music in the list. Even with specialized MOD editing tools, sometimes it seems you have to dig around for the right setting to make it to honor the looping-related commands in the ways you expect them to be honored during playback in a game. (For reference, I believe you achieve looping in IT files via use of the Bxx effects command.) In other words, if this doesn't seem to loop correctly, maybe it's because of the player and not intrinsic problem with the contents of the file. The only surest way to tell is actually trying it out in NeoLemmix or whatever engine this music is destined for, and
see hear what happens.
Anyway, as for the music itself, I actually think it could work, at least the OGG version. Sure, it's solo piano and very concert-y in style and thus very different from the typical Lemmings music, but maybe the better way to think about this one is to treat it like a special graphics level music. One may not want the "A Beast of a Level" music to be part of the regular rotation, but it works well as a special one-time music for that particular level. In other words, I actually like the idea that this is going to be different from the other typical music in use. It helps highlight the deliberate nature of choosing this music for the title reference. But I can understand other people finding it distracting for this one level to be potentially so musically different from other ones in the pack.
I call out the OGG version specifically because the IT version sounds inferior in comparison. It's probably impossible to fully replicate the OGG experience in the confines of the IT format, but maybe further digging around the Internet can find you at least a better IT/MOD version, including possible remixes that might work better stylistically with other Lemmings music used in the pack. I don't think it's worth our time trying to manually improve on this particular IT version, especially when it looks like neither you nor I really have the skills nor time to handle this sort of thing.
Still, I provided this updated version just to see if you can validate whether looping works in the game with this version. Then at least I know I'm doing it right, and can help add the looping for you whenever you manage to find other IT/MOD candidates. It's also fortuitous that this music is so loop-friendly, the ending and the beginning seems to loop perfectly as-is (ie. unlike other music where the ending tends to sound too final to be loopable).
