I think I got my parting wax from Composite structures technologies, but any store that sells fiberglassing materials should have it. (It's the green wax)

Batteries, in both of the BC's that I have built I have used 5 cell 1800 mah packs I am about to finish stuffing the batteries into mine today as I finish the engine installation (and the plane ...... Halleluah!!!!) but in the first one I built it took absolutely no ballast to get the CG right on the money. I did not use a voltage regulator but it is a simple matter of plugging the thing in after the switch and before the reciever. I have not used 2 packs on any jets yet, but in a larger aerobatic plane I simply plugged the second pack into a switch then into an unused channel in the radio and it worked fine.