We had water coming in thru the top of the door in a heavy rain storm. Had a channel installed over the door that made the water go down past the side of the door. No more water. Had to have the door replaced though. A lot of water damage from this when we bought it, but they replaced it free. It was a brand new camper.
We also had the condensation on the top aluminum strip, but leaving a window partially open takes care of that.
My 2014 Aliner Classic when fold down leaks when it rains. Southern California is in a drought but it has rained a few times in the last nine months that I've owned mine and it's leaked every good rain. It seems that water comes inside from the seam that runs across the roof where the forward side of the main roof comes down to rest on the rubber gasket that is attached to the rear side of the main roof.
I've cleaned the seam to make sure there's nothing in it and have found some small grains of sand, leaves, and twigs in there that have dropped onto the top while it's closed. I don't think they breached the seal but somehow water gets inside very rain storm. Enough water - quarts worth sometimes - that I have to pop-up the camper and run an AC fan to blow the thing dry. It's happened enough that I'm worried about dry rot on the bottoms of the forward bench seat areas as when parked that's downhill.
I bought a $80 cover from Amazon and put a blue tarp over the camper and then the cover over the top of that to prevent the leaks.
It seems that water comes inside from the seam that runs across the roof where the forward side of the main roof comes down to rest on the rubber gasket that is attached to the rear side of the main roof.