Welcome, Steve! This forum is bulging with helpful hints, helpful recipes, and helpful people! (We're bulging because, well, we like to eat LOTS of cheese!)
As Fritz alluded to, one of the significant issues with your mold experience is the small size of the cheese. I'd recommend not trying a natural rind until you get up to at least a 2-lb. cheese, and larger would be better, so that your rind-to-paste ratio is much, much smaller.
So, how do you avoid the mold on the smaller cheeses? Several options: 1) stay after it, scrubbing with vinegar or white wine to keep the molds away. 2) wax it. 3) vacuum-bag it.
Of the three, the last is by far the easiest, though usually 2) or 3) involves at least a bit of 1) at the early stages, because generally you want to let the cheese develop a bit before bagging or waxing.