Thanks for the answers. But I'm still confused. The molding I'm talking about seems to be a trim strip to hide the hinges for the basement doors. It's attached to the outside of the sidewall and overlaps the basement doors just enough so you don't see the hinges. the basement doors close against a rubber bulb seal. So I don't see how water getting in between the trim strip and the sidewall would leak into the sidewall or the basement compartments. But, I'm not very savvy on technical stuff, so maybe I'm missing something. Winnebago must have put the sealing (looks like clear silicone) on for some reason.