PorygonZRocks: I'm not sure if you know of me or not, but that knowledge would only help in giving you confidence in my offer. I have access to most of the file formats the KotOR games use and I recently just finished converting TSLPatcher from Pascal to Perl so I have the entire source code in two different langauges and can answer questions.
Had I even known this project existed (it likely got buried in all of the holiday and Episode 8 stuff), I would have been able to help out much sooner. Things like the .mod, .erf, and .sav files are all in the ERF format, while the .rim files are in the RIM format; both are similar, but have their tricks for writing the files. Also, with writing RIM files, you will never be able to get a 1:1 byte-to-byte ratio between the original game files and edited files... :|
I can be contacted on here via PM, on Discord (User name FairStrides, ID# 2148), or on Skype (though I'm rarely on that nowadays).
@peedeeboy: I realize that you guys are already past the fun of writing .2da files (yeah, the pointers part was fun, avoiding a 1:1 ratio and doing it the way Bioware did it), but I felt the need to correct you in that KotOR Tool does not do a 1:1 Pointer-to-Data ratio. It still uses a single pointer for each unique piece of data, with duplicate data being referenced by the original pointer.