How do I play multiple songs at once?

If you're making you're own song then to add a track use :0-15 to choose a track. Tracks can be used to have different instruments or for chords.

Um... I can't remember exactly how... but if you move the cursor over the BGMPLAY command and press the "?" in the top right of the screen, it will give you some instructions that should show you where to put channel numbers.

THX!