I have Events Booking 2.1.0 running in a Joomla 2.5.28 site.
When I am in an event's Detail page and I click on the "Purchase Multiple Tickets" button and next specify the number of registrants and I click the "Next" button, the spinning loading icon displays and just keeps spinning. I am not redirected to the next screen.
As replied via support ticket, there might be some javascript conflict causing the issue. Please follow the support ticket so that we can check and solve the issue