Egg/Hatchling Problem

I've been having this problem that I really can't figure out. The eggs in my incubator are placed apart from each other, buried about 3/4 of the way up to the shell, and some of them hatch out ok, while others die before hatching. Some of the eggs collapse, and others just turn moldy but either way I've given most of them 2 days to hatch (after collapsing or turning moldy) and after the 2 days is up I cut them open to find (usually) a fully developed leo inside!!! Can anyone explain this to me and does anyone know how to stop it?

I read the last thread about "rolling," and although I didn't know eggs rolled themselves while they developed, I am about 90% sure that none of the surviving hatchlings have turned the eggs, as I'm pretty good about getting them out and away from the other eggs shortly after hatching.

If anyone could give me some insight or advice on this, it would be greatly appreciated. Thanks.