I ordered a DMX Tabletop Controller and am looking forward to using it to control a follow spot that I managed to put together. One reason that I bought this model was the feature listed in the description, "9-pin RS-232 trackball connector port". However, I pulled down the manual and I see no reference to using the RS-232 port with a trackball. Where can I get information on attaching my trackball and mapping to a DMX address?

Chances are, it's just a serial port that has a generic mouse driver associated with it. I would say that if you're using a basic trackball, mouse, touch pad or any other controller that uses a typical 2-button mouse driver, you should be fine.

Not a fan of trackballs myself, but I certainly see the advantage of a compact space.

The rest of what you should need to know should be in the manual.