Adjusting the glass slide/tilt sunroof cover
WARNING: This page does not describe the selected car, but rather 31 other vehicles, including the 2015 BMW Alpina B7L, 2015 BMW Alpina B7, 2015 BMW 750i, 2015 BMW 750Li, and 2015 BMW 740i. However, it is still accessible from the selected car via links, so may be relevant.
Remove GAITER on left and right.
Close glass slide/tilt sunroof cover again (zero position).
Slacken screws (1) on left/right little by little.
Until glass slide/tilt sunroof cover (2) can still just be moved.