TOPIC: Category Access Level limited to default ones?

Hi there!
I want to use the category access level to display different event calendars and/or lists with respect to the users group and access level.
For this I have created a new group "STAFF" and corresponding access level and assigned this to a category.
Although the setting are similar to "Registered" it does NOT display the STAFF category events. When I change the category access level to "Registered" it works fine.

Is there a limitation to custom groups/access levels or do I misconfigured my ACL?

Stefan