SpaceMouse buttons not showing up in RH settings

My SpaceMouse Pro Wireless buttons are not showing up correctly in the RH settings - only buttons 1 to 8 are shown, however the SpaceMouse has 15 assignable buttons. Luckily there is a thread about the button assignment procedure here.

However I would still be great if one could just assign the commands simply in the Rhino settings, as this would be much less cumbersome and could be changed much quicker.