yea I dont know whats wrong either. I looked at your file and it I dont know why the head gets so big. For me that same problem was fixed with the input. I also followed the same DT kits as you did. I noticed however that a lot of your gemotry has a lot of inputs that arent cleaned prior to binding them to the skeleton. A wild guess would be to try to delete history on your geomotries before you do anything important to them like put blendshapes or binding. Just a thought dont know if itll work but just a thought.

-Dan