One thing that might be doable but be ridiculously huge is some primitive version of Dance Ejay 1. You would have to convert wav files to this format:
http://www.ticalc.org/archives/files/fileinfo/176/17685.htmlBasically, the music creator would let you paste small sequences of pre-made melodies, but since two cannot be played at once, every possible combinations of melodies, string leads, drum loops and bass lines would have to be recorded and saved as individual wav files, and to be played, the song would need to look through a list of each music file IDs to be played or something like that, depending of which combination of music riffs were specified in that song bar, then play the appropriate file with Asm(. The issue with this is that a 3-4 second wav file in this format is 22 KB, and if I calculated correctly, if for example you had 16 possible melodies/riffs, it would mean 64 possible combinations, assuming you have 4 riff channels, meaning that so few useable melodies would make the program total size jump to over 1 MB in size.
Just the size would throw people away.