I have Easy Profile Pro 1.3.3 on the freshest Joomls 3.3.5 with Protostar template. I found that buttons "Next" and "Previous" were missing in the tabbed view.
The reason is that there no elements with class "form-actions".
Have a look at tabs.js (for instance, line 54):
$('#member-registration .form-actions button[type="submit"]').hide().addClass('pull-right')
This code no longer works, due to empty selector #member-registration .form-actions
Removing .form-actions from the selector solves the problem.