I've had luck using liquid bandaid for small moldy patches, clean it well first. I don't know about covering half the egg, you might want to do a little patch every day until it's covered. for dripping condensation, make a little tent out of newspaper over the eggs and most of the dripping water will roll down the sides or be absorbed by the paper. As far as cutting, I've got friends who cut as early as day 45. I wouldn't do it that early though if you haven't had a lot of clutches to work with in the past.