deleting a user prob

No Delete users has not still been added.
So you need to delete users separately. If you delete an user in WP you also need to delete him on phpBB.
You can activate or deactivate users instead for the moment.
As asked elsewhere already, would be nice to have a ready class that delete users in phpBB.
When will be possible it will be added, and I will take a look maybe in something you have post. In the while any other suggestion is welcome.