I got the same problem on a UR There @migo. All works fine for some games, but I need to assign buttons for others.

Also, I can access the diag menu in some roms, but cannot select the settings (changing dip switches, etc).

Is there anywhere where I can get more information on this? If someone can point me in the right direction, I can write the changes and rebuild the program, I have MS Embedded Tools, and plenty of development experience!