Did you try and save the diffuse texture map of the head only? Try saving your project, and then open up default project again. Save the original default project head, and apply the new texture of the head your your project.
Then if that is the problem, all you have to do is redo the face and the body can be left alone. Also, highlight the avatar, and go to material panel. Highlight tthe head and lower the strength to 0. Then you can look at the head
of your avatar and see if there are any abnormalities in the head. Your texture map could be messed up.
