Do you use any sealer on the gaskets? What about the rear seal area?
With a stock oil pan I don't find a problem using the rubber seal on the crank end of the pan. It is the timing cover end that can be a problem (as you referenced). So, I just glue ( Gasgacinch) the foam down on one side and put a little silicone in the corners.
With a fabricated aluminum pan I use the foam on both ends.
I don't like to use the gray "right stuff" because it can be a pain to take apart and clean up if you have to disassemble.