Appointments+ Plugin setup is not working

I installed and setup Appointments plugin for mobyglobal.com and it is not working. My Google Calendar API app is using 0Auth2 credential authentication method and working fine. The issue is that when an open time slot is clicked, nothing happens using various latest browsers (i.e. firefox, chrome, and Opera). No error or Google calendar button or appointment confirmation. I tried testing with Login required and no difference in results. Please help.