Finally, I'd prefer a teaching assistant to log on in Student Administration Mode; how can I authorize him/her after he/she has been created?

To authorize a Teaching Assistant to log on in Student Administration Mode, you first need to change his or her job function. To do this, double-click in the column Job function and choose a job function other than Teaching Assistant. By default, staff can then log in to Student Administration Mode with the profile Student Administration (he/she no longer has access to the Teaching Assistants Webspace).