At least two files in this game use an unknown compression method. There are four known game versions, and the files differ for the most part between all four, which might be useful for testing (I can upload more samples on request), but for now I'm only attaching a sample of one file from the US version of the game.
I'm expecting a large number (several thousand) of GIM image files in the archive after it's deobfuscated. A method to properly unpack the archive would be a nice bonus, but isn't necessary (unless it turns out to not contain any GIM files after all).
(Just to help with tracking things: I also crossposted this to XeNTaX.)