Can you assign any keyboard commands with that device?
When you go into Screen4, and right click the button, there's a checkbox that says "Use Hotkey". If it has a large number like 65535, then no hotkey is assigned, even if it's checked. Uncheck the box, and then check it again. You can then enter the hotkey that you want.
The 2010 Screenset only uses the default keys for reset, cycle start, feedhold, and I think Stop. Any others hotkeys are different. The ones I used are listed in the 2010 manual. Be careful that you don't assign the same keys to multiple buttons.