Nice effort, for sure. I wish you all the best for this project.
On a side note (and I really mean side note), it's good you provide example musics, but
1. I think authors deserve to be credited. Whoever they are
2. "those three.mod" has 2 extra bytes. "classic.fc" has quite a few extra bytes too
I'm sorry I'm only running my good old FreeBSD 4.9, here. So I can't check this out. Still, I hope to read from this soon.
All the best,