ASSUMING low battery voltage isn't an issue (points don't care about it, systems like the Boyer are extremely sensitive to it; don't know about the Pazon):
As noted, it is caused by the fact that ignition occurs (spark) before TDC and throws the piston in the opposite direction. If ignition occurs extremely close to, or at, or after TDC, this will not happen. Note that for normal running, the spark has to occur before TDC but you want the starting advance to be as little as possible. If you set the max advance on the Pazon to 28, I'd bet the kickback will disappear because that will retard the start rpm spark (move it toward TDC) by the same 4 degrees. Do the specs for the Pazon call for setting it at 32 degrees of max advance?