Broken Quarter Window Roller Blinds - 528i
Found that removal and replacement is straightforward. There's a screwdriver slot on the top rear edge of the roller blind. Insert a thin bladed screwdriver or other tool into the slot at an upward angle. Lift the spring clip and pivot the roller blind out at the top to remove. Two spring steel clips hold the assembly into the door frame and it may take a little patience until you get the hang of it. I was told that repair is probably not an option before I removed mine, and found that to be true. I also heard that you can find them for approx $125 ea. but my dealer wants more than that for the replacement blinds. Pls let me know if you find them cheaper anywhere else.
Hope this helps and good luck!