The ?? would tell me either the translation is missing, or it's trying to use characters that don't exist on your computer. It shouldn't stop things from working.

There are 3 different plugins listed here - http://www.nvcnc.net/nvum.html
Probably worth trying them all, to see if you any connect to the controller.

And just to cover the basics, you have connected a suitable 12-32VDC supply to the controller?