We are currently using the DEMO version. The Calendar/Navigator is implemented on our development server and works fine. Once implemented in our test environment on the production server the problem occurs.
The calendar will work fine (Context Menu, Event Click, Remove Event, Move, Resize, etc). Once a month on the Navigator is clicked the Calendar disappears and most of the sites functionality fails. Clicking on the Navigator a second time, make the Navigator disappear as well.
Let me know which code elements you would like to see and I will post it.