If you would make eyelids for animation in games or movies, if you want to unwrap the model in zbrush and bake a normal map in zbrush. The eyelids, you would create more geometry that goes into the socket and that the animator could pull out right. That wouldn’t project well when you project detail back on a low poly mesh.
So do you have to create diffuse and normal map first in zbrush then go out and cut in a bit above the lid then unwrap that part in another program and try to blend the seam. Or is there some better way, I hope you get what I’m asking.