Submit button does nothing on a registration page

I am trying to make this plugin work on a fresh wordpress installation (4.2.4). Everythinkg works fine but when I try to click SUBMIT button after filling the event registration form, it does nothing. Not even a page refresh. I created fees to make sure I got everything. No error message, just nothing happen. Tested in multiple browsers. Thanks.

https://www.ads-software.com/plugins/event-registration/