I have a new home (2001) in new england. the walls are all blue board with plaster. In only one bathroom, the paint refuses to stick only to the areas that may have had joint compound used like the seems between ceiling and wall, and covering screw holes. I have scrapped, sealed with primer, rescrapped and sealed with shellac, painted with no primer or sealer. To no avail, the paint and whatever under coat peel off in one layer after 6 months or so. It is the area right over the shower, so it is definately moisture related. Any idea how to make the paint stick?