Recently active topics in PBwiki tagged with permission

My free Wiki has 300+ members. When I migrated to 2.0, they all became Admins, and I spent the better part of a day individually changing them to Writer, waiting for the page to refresh, and doing the next one. Now I find I have some wise guys/gals changing things like the notification person in the Settings area, so I'd like to downgrade everybody but my 3 fellow Admins to Reader. Is there any way to do this en masse, or must I dedicate another 3-4 hours to the task?

It seems that only administrators can add items to the plugin calendar. How can I allow all writers to add items? I have tried changing security levels on the page, but that doesn't help. Can you help?

Is it possible to use screen shots from pbwiki in a publication? I am writing an educational book on using Web 2.0 in education. I would like to feature pbwiki and use screen shots to show the step by step instructions for creating a wiki.

Is there a max number of allowed administrators on one pbwiki site accessing a page at the same time? I have 25 administrators in a training, trying to post comments; some administrators were unable to gain the permissions needed to comment on a page? What would restrict their access, as an administrator, to not allow them to have permission to add a comment?
Thanks....