My friend took Zippy to a PT in Albuquerque Monday, and they walked him on the water mill. He came home with lots of new exercises to do. Zippy's walking is slowly improving. He's walking through simple weave courses and stepping over small items to help him learn to pick up his feet. My friend said walking in a couple inches of fresh snow is actually really good because it also is helping Zippy learn to pick up his feet.
I have a short video I will put online one of these days from last weekend, and will likely get another video this weekend for comparison of how he's improving.
Thanks for all the well-wishes!