Let me admit that I still do not fully comprehend roles in Moodle 1.7 onwards:
My course-creators have the right to change the start page of my 1.7.2, can add discussions to /delete from the forum and play around with blocks, too (though upgrading from 1.7.1 to 1.7.2 did help to get them out of all the courses' memberlists (Hurray!)).
I think I have now tried (un)checking everything that sounded or looked like the right checkbox - but ... nothing seems to work. I now believe that I've been either too dumb or not daring enough to change this ...
Can someone please tell me which checkboxes to tick / un-tick where in order to restore something roughly resembling course-creator 1.6 rights for the start-page (that is: no rights at all but to answer admin's posts in the forum like all the other users)?