@ GoldenPincers
The Modpack.exe extracts some files but not the archived .BIG files.
After Ryder made the ROL BIG Archiver, you can now extract more of the content that was previously hidden.
As far as which one to mod, that's a good question - we still need more testing.
I know Motter28218 did his modding pre-RBA, maybe he'll post here again and explain what he knows.
My guess is you could try a simple mod and test it with both XML files one after the other to determine what works or doesn't.
RBA and ROL modding in general still needs testing and probably some new utilities or integration with existing programs.
I'd like to see people figure this out as I have limits with my skills and I initiated the
Upatch project for this reason.