Event submit button missing

I would like visitors to be able to add events, so therefore I created this page: http://atletiekkalender.nl/voeg-toe/nieuwe-wedstrijd/

However, for some odd reason the ‘submit’ button is missing, which should be at the bottom of this page. When I change my theme to the default WordPress theme, it works fine. So apparently I have to look for something inside my theme files?

Many thanks for your help.

http://wordpress.org/plugins/events-manager/