Well, this sure sucks!
After that hellacious backfire you described John, did you check to see if you still have compression on both cylinders? I ask only because it sounds as if your spark was somehow so far advanced that I'm hoping you didn't hole a piston.
I'll keep my fingers crossed that that's not the case, and that it's just a faulty Pro-Com unit, and that your old unit will end up being the fix.
