pavlova

Can you please describe what you mean by "seep in?"

The whites may have been over whipped.

I'd say moisture generally, by seeping in do you mean it's soggy, or just sunken in the middle? If it's sunken, do not fret, that's totally normal. I leave the oven closed till the meringue's done, and the door open as it cools. Don't worry about cracks!