First of all, THANK YOU for this plugin ;).
I have got two feature requests you might consider in an upcoming release:
- Make your plugin compatible with WPML (multi-language content support): http://wpml.org/
- Add new options in the options list to set custom class names to the access denied/permitted pages' body. Something like "custom body classes for Authenticated Users" and "custom body classes for Anonymous Users" text boxes. By default we could use something like "accessdenied" and "accessgranted" plus auto-generated classes like "group-groupname". This will let us more control over the page appearance.
That's all :).