I couldn't get the video to work, either. But, I thought I'd share my thoughts and experiences with a new stability ball I bought. I think it's a Reebok, and it's got a little bit of sand in the bottom of it. It doesn't change the "stability" part of the ball, but it does make it so it stays put when you put it somewhere. This was a big problem I had with the stability ball - I had a hard enough time trying to balance on it for some of the moves, and then, when I tried to get on it, it rolled just out of reach! With just a little bit of sand in the ball, it stays put and it's easier to use.
I also had a problem because I couldn't find any balls that were less than 65 cm. I'm 5' 3", and this was just too high for me. This Reebok ball is 55 cm. and sometimes I think it's too small, but I can do the moves on the ball easier with it because I can physically manage it better.