Hello Cerealsurfer,
thanks for the advice on the wind deflectors. No, I have no deflectors so far. But actually I did consider buying some ... maybe I should reconsider.
If I can manage I will bring the car to the local Swiss dealer (fortunately just 15 miles away) an Monday and see what he thinks.
The crack is quite large. At least 7 inches :-( What are the risks of driving longer distances (probably with no hood in order to avoid further damage)?