Insert Meta by formidable forms

I am using formidable forms and they allow to turn a form into a post after filling it out. For this the offer a custom field to form fields mapper for additional fields. As Events is a custom post type are the fields start date end date etc. actually custom fields? can I map them just like that? And if so what are the keys of these fields.

Regards

Max

http://wordpress.org/extend/plugins/event-organiser/