[Program] FSYS Opener

[TheAmazingSnivy]

I found this page, which includes a FSYS extractor (gcfsysfd): http://hcs64.com/vgm_ripping.html

That might be a first step in the right direction. The problem should then be reduced to parsing .fdat files.
There are programs like in_cube which play audio extracted from FSYS files.

Now, look at this thread. User revelation tells us that Pokemon Colosseum files are derived from a known archive format used in the "sysdolphin" API from HAL labs.

Which leads us to this thread. Aha! Someone trying to do something similar to you, but for SSBM! This post in particular is informative. Read through that thread, the OP details his progress and there are some screenies from page 2. (51 pages, beware!)

Hope this helps.

You've been a real help! Thank you for the links. I'll look through them right away.
In_cube is a .dll file, but I don't know what it goes to... anyone?