Ha ha! I'm glad you figured it out! Don't feel embarrassed- that little water-well cover was left in my box for my first two hatches, before I realized it was supposed to prevent drowning...
Fingers crossed for a good hatch!
Hmm, strange- I have a Brinsea Mini Advance as well- and little cog-wheel turner worked for me- does the weel still turn, but the eggs don't?
Make sure the eggs are placed in the little egg-shaped cutouts, with their shells directly touching the plastic- then check the intervals that the turner...