I own a 2008 Smart Car for two passion. The black retractable roof shade does not move back and forth. I found a spring on the drivers side floor mat that I think is part of it. Is the roof of the car glass and does the roof retract or move in some way. Pardon my ignorance. I just bought this car yesterday and the couple I bought it from is still looking to find the manual. There is also a long string hanging down from the the retractable cloth. Is it difficult to fix this?