[ocimbote]

Overall, I'm impressed. Very much.

Now, I'd love to see a picture of how a hand is supposed to sit above or around this trackball because I can't picture how fingers can comfortably reach the 4 buttons just by looking at their location on the device.

Which leads me to the personal opinion: I think I prefer the design of the testbed over the final iteration. Buttons are missing, I know, but... Here I stand nonetheless.