Disklavier

Please recommend a midi editors suitable for use with Windows and a disklavier.  

To start I'd like to try a simple and inexpensive editor.  I'm hoping to use the software to do two different tasks for downloaded midi files:  1) converting the midi into an .mp3 or .wma file, and 2) changing a particular track in the midi file to channel 1 or 2 and then saving it onto my disklavier.  I'd like to do the latter so that I can play back a midi file via my disklavier with emphasis for a particular vocal part (as a means of mastering it).

I understand that RePerform recently has been released.  It sounds wonderful, but I suspect it's both more complex and more expensive than what I need.

Thanks,

Lloyd Randolph