How about registered users? There does seem to be options for adjusting front end editing, but even when I'm on the site as an admin, I don't see any kind of "Add Event" option.
Of course it was possible to change the settings. And the problem was solved.
What I am trying to say is that, although the calculated settings appeared to be set as "Not Allowed", I had to repeat the process of selecting the "Not Allowed" option for all the actions.
I think this operation was redundant but it was the only way it worked.