Same clutch, here's a closeup of the one with a dark spot:
It had this from the beginning. It started out as a noticeable bulge. The moss sticks to it and it's a pain to get it all off, so I can't really tell if there's fungus there or not. But the egg is still growing and looking good.
I hope to catch this one pipping so I can be sure which hatchling comes out of it... just out of curiosity, to see if there's anything out of the ordinary about it. :)