Small question: Is it possible to use multiple BGMs at once?

Yes, BGMPLAY has the track number as an argument. You can play up to 7 song at the same time. You can even use some tracks to do "sound effects" using MML. You need to define your song with BGMSET before using BGMPLAY. Example BGMSET 128,"CDEF" BGMSET 129,"BBBBBB" BGMPLAY 0,128 BGMPLAY 1,129

Unless you use one of 30+ built in songs. Also, pressing the question mark button while a command is highlighted will tell you the arguments and a brief description of any built in command, useful for quick reference :)

>You can play up to 7 song at the same time. I think you meant 8 BGMs, since 0 indexing exists.

Thanks, guys! This really helped.