convert normal post to event

Hi everybody and thanks for the great plugin!
I’m trying to migrate an old WP installation wich has been used as kind of events calendar and has many posts (with picture and some custom fields) each representing one event. The post date is the event date. Is it somehow possible to convert the posts to events (preserving the custom fields, if possible). Any hints how I could achive this are appreciated. Thanks in advance!

Best Regards,
Tony.

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