Problems with Appointments + after upgrade

Hi –

I added the WPMU Dev Dashboard to this site today, and upgraded to the latest version of Appointments+ (I had previously upgraded to the beta version), and things appeared fine. Settings carried over, confirmed appointments, etc.

I’m now attempting to make a test appointment, but when I click a time slot, the little loading timer just sits and cycles. I never get to the next step.

The page is: