I've added two LEDs to the board to help with checking the power circuit state. One LED is nominally orange and it's whether or not the relay/contactor is (or should be) on. The other is nominally red, and it's an indication of the GFI flip-flop state. If one LED is on, the other must be off, but both can be off as well.

This will allow you to potentially do some testing and troubleshooting without having the HV board hooked up. If you power the Pi other than via the HV board, the pilot generator, pilot generator feedback and the AC voltmeter won't work, but you can still perform the GFI self test and power start procedure, including petting the power watchdog.