I want to put wrinkles on my character’s face and I want to use texture paint to draw the wrinkles (the current CVS build has very nice texture paint capability). I want to use a 512 x 512 pixel image for the face otherwise painting is too slow. But when I used the texture painted image in a texture and map it to UV then it applies the wrinkles to the whole body. Is there a way to create a UV map region for the face and then a separate one for the body so when I apply a texture (from the materials panel) I can specify which region the texture is applied too?
I dunno really if I understand it right, but maybe if you seperate the wrinkels and the other body, by making another texture, that lies over the other skin texture and then put both on them on your object, and only press “Nor” on the Wrinkels texture, wich is called a Bump map, it might du that. 
Set the body and head to be completely different materials. Of course, you’d want to make them similar, but that’s how I would do it.
I am testing the above suggestions. I will later report if something works for what I am doing.