@ coldwave;
"What is that orange on the head ?"
I painted on the model using ZProject in ZBrush and saved as an image but the image was very Blueish so i did a quick colorcoorection in PS.

@hammer.horror;
I always use PS for the final texturing, the lining up is indeed no exact science, however i experienced that if the model is good enough it lines up pretty well.
I usually grab some keypoints; Eyes, top of head, point of nose, mouth and chin and start painting in the texture and it lined up reasonably well.