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Great tips above. The only other things I'd offer is to see how long you let the egg warm up after you put in the platesetter and stone. If you put them in cold, you're going to need a good bit of time for them to get up to temp of the egg (I put mine in 500 degree oven while egg is being lit and getting up to temp so it shortens time when putting them in cold). Also, assume you were using new lump? On re-used lump, my max temp is usually 500-600. Regarding your crust, I started out making pizzas with the same problem as you and it was how I was stretching the dough. Make sure to make a rim for the outside crust and do not touch or stretch the rim from there. Stretch from middle outward but don't disturb that outer rim. That should help you get a light fluffy crust. Best of luck...guaranteed they'll get better with time.