Using the beta here... So far so good. While only parts of the configuration are currently working, I can at least now officially set the top buttons to do whatever I want them to. Which you know, should have been the case with the shipping product waaaay back. Problem is, I've gotten so used to not having functionality from the top buttons, that I have to retrain myself to their existence.
Also, ch_123, the scrolling functionality of the Slimblade had no software dependency. You could use the trackball as a standard 2 button trackball + scroll without any special driver or software. I was for a long time.