I think they accept that it was, as you say, installed by an idiot, as he no longer works for them. In fact it was just one thing after another - perhaps as my wife said, I've seen too much. I was on leave when most of the work was going on - it's still not completely finished. The only way I can see of rectifying this is by removing the roof and reinstalling it, but this is something they are unlikely to do. It would require a completely new roof as all the holes have been drilled in this one to put it in the position its in at the moment, not only that but replacing it would also expose the kitchen which is open plan into the conservatory. Undoubtably this is the best solution but it also likely to be a long arduous one, and frankly I've had enough. This problem is the last outstanding one and the shortest route is in this instance the one I'm looking for.
Mike.