Likely contains the BGM used in the game map (duh). Said BGM is unique in that the map is divided into 9 sections, and each section you click on triggers a different combination of instruments. If you just let the song play, without clicking on any section of the map at all, you will only hear the bass guitar. Clicking on the middle area adds piano accompaniment, clicking on the left area adds violin accompaniment, etc. This is likely programmed into the game, not the song -- i.e. the song probably exists accompanied by all possible instruments, and the game probably just mutes each one until the appropriate map section is clicked on.
This file is only 24k in size, so it's entirely possible (and somewhat likely) that the instrument data for it is stored elsewhere on the CD. It's certainly possible, though, that this file alone represents the entirety of the map BGM, as I could probably duplicate it in MOD or S3M format in a like amount of space.
If anyone with more technical expertise than I would be willing to take a look at this, and see if they can figure out how it works, I'd appreciate it. If it's possible to rip the music from the Coloball CD, I want to do it. If not, I want to know, so I can try other methods (e.g. hooking my PS2 up to my computer).
Thanks in advance!
Note: if anyone from Vanpool is reading this, I WANT A SOUNDTRACK TO THIS GAME!! I'll pay whatever you ask! Just gimme gimme gimme!! (: