>... The brsar is like a zip archive it has all the fun stuff inside as for decompressing it
> I do not have a clue on how to decompress it. Nintendo always spoils the fun.

FYI: The "BRSAR" file structure has been figured out. There are two old tools that do this (see http://hcs64.com/vgm_ripping.html under "brsar tools")
They are old tools, but they come with source code.
They won't convert/export the sound files in the "rv_forest.brsar" archive, but they will decode the archive format (and complain that it doesn't understand the individual record format)
(there may be newer tools, but they usually focus on specific games and don't come with source code)