[Plugin: Events Manager] Search Form with checkboxes- AJAX

i am looking for a way to make the Search form more advanced. Instead of having a dropdown I would like to add checkboxes and when checking them the event list changes(basically shows events from checked eventcategories). Best would be to have it be in Ajaxed so page is not refreshed.

Is there a way to create this? or is there something written for it?

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