Yep weather sealing is always tricky, I was planning on having a raised lip behind the seal that goes up into the roof cavity with a second seal on it so any water would have to go past the first seal, up and past the second seal. Hopefully that would be enough to stop it. There's also be the soft top tent material to get past, maybe even a wind deflector mounted on the body that the roof leading edge drops down behind, lots of options

Cheers
Steve