Undefined offset: 0 and using post_type post categories

I am trying to use wp-fullcalendar with event manager.

Both are installed and i have attached the post category type to the event post_type using:

register_taxonomy_for_object_type('category', 'event');

I have two issues that maybe you could help me with:

1.

If i have an event and use the category type i have registered from the post post_type the calendar only shows the event if the “all categories” option is selected, it displays the list of categories in the select drop down but selecting the category type of the event results in the event no longer displaying.

Do you have any ideas what the reason for this are and how i could go about rectifying it?

2.
The calendar loads on the page with the two following errors –

Undefined offset: 0 in /var/www/…/wp-includes/plugin.php on line 767
Undefined offset: 0 in /var/www/…/wp-includes/plugin.php on line 785

Do you have any idea what is not being passed that is required?

Any ideas would be gratefully received. The plugin seems to be very good.

cheers

http://wordpress.org/extend/plugins/wp-fullcalendar/