I have a 2013 Leprechaun 280 DS and have a similar problem. On the bottom of the main slide there are a few gaps in the seal. They seem to be there for a reason. The problem I found was in storage. My main slide is in the drivers side and my storage spot is uneven and slopes down with the passengers side being the low side. When there was a large rain I noticed water running on the floor from the drivers side to the passengers side. It took me a little time and that's when I found that the rain was entering the front gap in the seal. I leveled the motorhome and have never had any water coming in as long as it's level.
Sent from my iPhone using Forest River Forums