Final update: all done. WB3.2 installed and working. Things I learned here:
1. As unlikely as it sounds, the Buddha firmware somehow got corrupted between when the board was manufactured and the DOM loaded, and when I plugged it into my A2000. I don't really understand how this can happen but re-flashing seems like it should be an early troubleshooting step not a late one.
2. It's a bit weird that the LED pins are the opposite of what the A2000 case LED is. I'm not sure if this is because other cases are wired differently but it's a small thing that should be more clearly pointed out, perhaps on the instruction sheet.
Otherwise, I'm delighted. This thing is seriously fast! From power on to workbench in seconds.