My car developed the usual roof not opening problem , the rear section stopped working not opening , causing a fault , my local BMW dealer solve the problem apparently, now the car is back in the shop with the same problem and I have Just been told The problem is The rear windscreen needs replacing , why would this be anything to do with the mechanism of the roof , The dealer has told me that they are waiting for somebody to replace the rear screen , I have no idea what this has got to do with the mechanics of the of the boot any advice would be very welcome