Well, I'm absolutely sure that something (probably one of those pak files) is saving interface files - *but* that if I delete all the interface folders then it reverts to vanilla. Yet if I put them back, even with new files, it goes back to whatever was the first one I did.

It basically means we can easily add GUI's to the non-roman factions, but we better have them perfected when we send them out since it seems to be a 'one-shot' thing, unless each player fully unpacks the paks and erases the pak file. Then it recognizes changes upon every reload.