Hang tight. I'm working on a major rework of the spreadsheet.

Safety Note: I've noticed the CDI can sometimes fire a random spark here and there. Sometimes a bit after you power it up, sometimes after you remove the power. I think this is probably a hardware issue due to the way the circuit is constructed, I don't think anything can be done about it in software. So be careful! You should power up the CDI before you start messing with the engine and stay clear even after you shut it down.

One feature I'm working on is a software kill switch. I'll probably have the unit fire a few sparks right after the engine stops just to make sure the cylinder can't accidentally fire from a random spark. This probably won't be 100% either as gas could vaporize over time and create fresh fumes in the cylinder.