I just tried the demo site logged in as DemoAdmin, and I still couldn't see a way to add appointments. There was niether a popup over the time slot I hovered over, or an 'Add Appointment' link below the calendar. There is an 'Add Appointment' button at the top of the screen, but it just links back to the calendar page with no way to trigger the new appointment.
Again, what I'm most interested in is the ability to block out time that the service provider is unable to take appointments. A way to do that while logged in as the admin would be most valuable to me.
I guess the workaround in this case is to create a user solely to submit appointment requests for time the service provider will be unavailable. It would be a bit of a hassle to have to deal with two accounts, and the extra step of haviong to login as the admin just to approve those requests. But... it could possibly be a usable workable for the short-term.
Likewise, editing a submitted appointment would be useful as well, but it doesn't make the module unusable in the situation I'm trying to address.
That said, please consider this as my formal request for both features in a future version of the Booking module.
...rick...