hi, when we got the van the dealer threw in a new dorema awning, the first 2 or 3 times it was used it leaked like a sieve, in fact the first time there was more rain inside than out but after it had been soaked and dried out a couple of times it was fine. had it 6 years now and had no more problems and is bone dry even in the heaviest rain.
so I suppose my advice would be to leave it to cure it's self.