John, have you try Jakes timersoftware with a LED or bulb instead of a HV-board ?
If the problem with Jakes software is there, you must have the same problem with a LED or bulb.
The LED or bulb have to stay on, same like the timer the HV-board is set on.
This test cost less, the (HV) transistor can't be damaged.

I have a wrong candle in the Homie (big one) and can't use your sparkcap.
Monday I can buy a new candle, over the weekend they are closed.
Maybe I can try the old sparkcap from the flywheel ignition.