u fix the mapping by making it so you can see the tongue in the mouth not the roof of the mouth. It is below the centerline so unless the head is tipped back you will never see the top angle of the mouth. look at a pic with a mouth open that is looking straight ahead.
also you guys should actually figure out what your making and rough in the rest of the head before it turns into a big pile and you lose interest in it because it's hard to work on.