In case I put the respective query just below the first HeaderTab everything works fine . However, as I put
this query into the second HeaderTab section to make place for the result format calender in the first section
I just get the borders of the display . Since option  is not possible (calender format in the second
tab) because of the way the calendar loads and due to usability consideratations it would be cool to have a
timeline into a subpage but I believe this should only be a temporary solution.
The problem started with the upgrade to MW 1.17.0. I think it cannot be a SMW issue since it worked with MW
1.16.5 and SMW 1.5.6 and does not work with MW 1.17.0 and SMW 1.5.6 (my wiki) or SMW 1.6.0 (referata).
Cheers and a good day to all of you