I've tried to create some soldiers with black skin and therefore used the setFace command in combination with the three available african faces/heads:

"AfricanHead_01"
"AfricanHead_02"
"AfricanHead_03"

The skin colour of the neck and facial area changes properly but the one on arms and legs is not adjusted the same way. It seems to get a little darker but it doesn't match with the facial one. It makes the unit in question look a little weird. {F23152} {F23153}