thanks for doing that, that's brilliant!
did you try it with my protracker extension as well? only i thought the sound effects functions might interest you, since there are currently no sound effects in your game and my fx engine allows sound effects to automatically mute music channels temporarily.
although for anybody interested, PuzCat doesn't use those functions, but rather it uses AMAL to do the sound effects. I wrote the fx engine after PuzCat using a similar idea, after it seemed to work so well.