BMW Repair: drivers door window, series bmw, bolt nut

Question
hi i have a 5 series bmw and had all my windows smashed on my car they were replaced by the rac through my insurance but a few weeks after being done the drivers door window glass drops when you open or shut it it wont stay in the runners it just keeps dropping to bottom of door.  

Answer
Hi Jez,
There is definitely something wrong with your window regulator( it holds and moves the glass at the same time).
As to what is wrong, you or somebody have to remove the driver's door trim and soundproofing/vaporshield to find out.
It could be a simple thing such as a loose or detached bolt/nut. Or the window regulator may have prematurely gone south.
If you plan to do the checking yourself, tell me so that I could give you detailed instructions. Also include the year of your car, there are so many 5 series...
Tino