Vampire skin colour can't be changed

This i just found out, my vampire's facial tint can't be adjusted at all. In human or vampire dark form. 
Only if I change her back to human I can change her face. 
When I click on her face when she is set as a vampire, just the face presets pop up. Not skin tone. 
So now she can't have a different skin tone than her normal self. Which kind of defeats the whole dark form idea. 
I don't use any CC or mods with this game. on Windows PC. all packs