Found the problem. It turns out their is no voltage at the A/C out breaker until it is loaded. I had a fan plugged into an outlet on that line, and so even though the thought of a load did occur to me, I assumed that was accounted for. Well, it turs out the GFCI outlet box I was using will not work with the way the inverter produces power - not sure why. But, one thing I did notice is that there is about a 2 second delay between presenting a load to the A/C out L1 (or L2) before power is delivered, then if you turn something off and back on again it will be immediate unless you wait about 30 seconds or so, and it goes back to the 2 second delay. Maybe this messed with the GFCI, I'm not sure, but I replaced those receptacles with non GFCI receptacles and everything works now. Funny thing is I suspected those GFCI outlets would be a problem at some point, but they were a no-go from step 1.