Hi Jason,
Thanks for reaching out here on this. Yes! There different ways that you could accomplish this. First, you can simply hide the new event buttons on the calendar by adding some rules to DayBack's CSS theme. See the second modification described at the link below to hide the new event buttons:
http://www.seedcode.com/pmwiki/index.ph ... eMaker.CSSAddiitionally, DayBack will definitely respect users' FileMaker security privileges, so that if they don't have access to create new events, they will not be able to from the calendar either. If they click a new event button, it will appear as though they can create an event, but the event will actually not be saved once DayBack attempts to create that new event in the database.
I hope that helps! Keep us posted with any further questions.