For interior door cards and other trim pieces I use the 4' x 8' fiberglass panels that are found at Lowes. Think they are used to build showers. I use it because it will not absorb moisture and swell. Lately I have had to repair a few panels due to the vinyl not sticking to the card. The glue I'm using is Weldwood Landau Top and Trim that I get from an upholstery supplier. My procedure is to coat each part (card and vinyl) then wait several minutes and stick them together. They seem to hold well but 6 months later they come apart. What am I doing wrong?