Error when adding event

Hi
I recently moved the site ihbc.hu from a hostgator account to my account. Since the move, the Events Manager plugin / Add Events isn’t working.

Now when using ‘Add Event’ I see the following errors and and the page won’t load properly:
Warning: Creating default object from empty value in /home/sjitcons/public_html/ihbc.hu/wp-admin/includes/post.php on line 641

Warning: Invalid argument supplied for foreach() in /home/sjitcons/public_html/ihbc.hu/wp-content/plugins/wordpress-seo/admin/metabox/class-metabox.php on line 1056

Any ideas as to what could be causing this?

Thanks
Ai