Yeah, I went through and re-cut and sealed the flex watt on the 'bator, eliminating the sheet that ran across the floor (and was thus susceptible to moisture pooling beneath it). It's back and operational, but I thought it was worth mentioning just in case anyone else had the same condition I went over three months without realizing the risk.
I doubt the powder coating would make much difference, unless it's latex based and thick enough to be an effective insulator. The important part is to make sure you've got the bottom end of the flexwatt completely sealed (just the very end of the metal strip that peeks out of a cut strip), and not in a location where any amount of moisture can accumulate beneath it.