How did you insert him into the scene? I know with AfterEffects you can do pretty much anything you flippin' want with a few mouse clicks, but for me I'd have to render Arex separately with a green background and nothing else, and later in my video software of choice (Wax 2.0) key out the green with the original footage being the underlying track. Do you have a guy in a green suit do all the motion for Arex, or do you just paste him in to the scene without any sort of reference?