Looks great, lamb! :) I would soften the contrast a little between the dark sides and the middle, but other than that I'd say it's about done. :-D For practice with painting lighting, you should get your Poser artist friend to render a few images with different lighting environments -- like with a key light lighting the front right and a rim light lighting the back left, or something as dramatic. This will add depth to your images right from the start and give you a challenge in painting highlights and shadows. ;-)