Ahh, that was it. I didn’t use the EMM or BSR files from Sloth’s model. I added both of those and the body model was fixed but the dress flaps didn’t move. So I used the EMM from sloth’s model and the BSR from the original skin and everything seems to work fine now. The textures are messed up but I’ll have to fiddle around with DDSrefedit for that.
Thanks a lot hecz!