CincyGus, I wondered if that may be part of it. The slide is long to accommodate a sofa and dinette, plus it's kinda deep as well. When extended, there's not nearly as much angle as with the smaller one that doesn't collect water. In a light rain, it all rolls off, but when it rains hard is when the flow overwhelms the slight angle and pools up. Since it was a very well-known dealer who did the work, I may ask if there's anything they can do. I'm not sure it's worth more holes, though, if it would require remounting.
