As a developer of Music software, I have recently been updating my program HARMONY and would be interested in this type of project.

You can try it out by downloading from www.greenhedges.com

I have been looking for a better and more general 'internal' representation of tunes than the one my program currently uses, and have been considering the use of XML, at least as output.

My program was primarily intended for sound, specifically the adding of chords to a tune, and the scoring facilities grafted on later are not really adequate for more than simple tunes.