I'm having problems as well. The update did fix some things for me. For example, before, turning the knob would move the mouse, and pressing the button would be like clicking the mouse. That no longer happens. However, I think long press is still broken. I can't get it to do anything, except for one brief moment in time where it worked. I think it might have something to do with whether the PowerMate software is in the foreground at that time. Additionally, I can't adjust the brightness of the LED on one of my PowerMates (I have two; the other one is fine, but I think they might be different hardware revisions).
Hopefully their commitment to make a Bluetooth version means that they will continue to work on updating the software.