Fix: membership access filter would occasionally cause the wrong content to be blocked.
Enh: Moved load of admin page meta to add_meta_boxes action.
Fix: Would sometimes incorrectly list all content if no posts were accessible for the user id
Fix: Use the stored sequence post list ($this->posts)
Fix: Correctly identify cases where there are no posts available to list for the current user.
Fix: Would incorrectly load settings & posts for the existing sequence object.