There's something with your legs that always seems to be separated from the body. Basic movements training will help you a lot, like walking.
Stiff, and you used the same size on the brush when you zoomed in? It looked like you did...
On the finished one at the end where he leaves via bottom of screen and enters via top of screen, did you get that from JC's part in the SL Portal Collab?
i think you need some work on the basics ,like stifness and choppyness ( walking ;) ) check out some tutorials, but i like the background on the first one