I'm hoping I can help you see it from the horse's point of view. He gets grain in his stall. If he leaves, how will he get grain something it seems he's particularly fond of. His stall represents a lot of security. As for the pawing, someone has inadvertently trained him to do this. He paws, someone hurries to bring his feed. This time when you feed, take his to his stall but don't enter it. Instead turn your back and slowly walk away. He may paw in a frantic fashion for a bit but just wait him out. In his confusion he'll quit. That's when you give him the feed. If he starts again before you can, walk away again. Spend the time now to fix it and advise others how to do it. He's likely using his shoulder to try to push the stall walls over - separation anxiety. If he's the only one in the barn, he's not with the security of the others and he doesn't want to be dinner. As for the peeing, a horse will pee when stress is relieved. Or if inside too long.
Last edited by Saddlebag; 10-01-2012 at 12:23 AM.