The starfish can move pretty much anywhere over the bottom of the tank, and over the bottom third of the front glass. It moves sloooooooooow, but if you watch it you can see it moving.
As far as Beta testers go, everyone on the forum is a Beta tester.
That's the job of everyone here. We all give suggestions on the forum and try to help. If you mean directly to Jim, only a handful. It can get to be a time consuming process. I think I have installed and deleted 5 different versions in the last 2 days. Jim has put in many hours trying to get the collision routines refined to the point that he is comfortable with them.