I got another tough question for you all. It turns out that some of my archive files are actually located in "panepon.szp", which, upon googling, appears to be a mostly untouched format. So into the hex editor I go. Turns out it's Yay0 compressed, which I was able to decompress with a tool I found online. But... the problem is it doesn't support recompression, and the tools that supposedly do are built for luigi's mansion and don't actually compress my file properly (game crashes when trying to load).
I know the decompression is working fine, since it decompresses into an identical .rel file which is also within the game (but unused). I'm wondering if anyone has a tool that does the compression. It's frustrating, since the particular files I'm trying to get at had 4-5 'decoys' which are the same files, but unused. The real ones are behind this compression. And the game won't accept the uncompressed format nor yaz0.
Help? Or am I going to be learning yay0 encryption this week?
Edit: I should mention that the yay0 tool that works is yay0dec from: http://www.amnoid.de/gc/
. The one here on romhacking.net doesn't seem to work.