At the moment, the TXD for custom models in MTA are screwed up, but DFF's work fine. It's tested and a known bug on the forums. But in future, I'm sure would be fixed. I'm working on my own gamemode too, with it's own minimodes. He was in fact inspired to go on to create that gamemode cause of me

. I guess Slick's one focuses way more on cars.
Although I can't give you much of a hand because I'm still working on it and the core is almost complete, hate to throw away way over 2500 lines of hard work

Anyways, I'd think it would be more effective to include each custom model as a separate resource, because then you can use that custom model for any gamemode. He didn't mention I'm making a gamemode though? But anyways, goodluck guys
