Scratch that, the problem isn't the mp characters anymore. I can switch to them now. They don't have a body but they work alright. The clothes made for them aren't buggy so yeah.
The Zapatero Poncho still won't put on though. Even as a mp character. I don't know if I screwed something up or if it's a bug. Somebody should look into this.
I was wondering why when I try to put the Zapatero Poncho on Arthur, nothing happens. Do I have conflicting mods or is it because I can only put it on MP characters?