[Plugin: wpNamedUsers] Permissions don`t have any effect

I just tried the plugin wpNamedUsers. Off course the plugin does not work: I tried to set different permissions and denies. But it had no effect to the real permissions of the users.
E.g. I wrote an article and than I denied the permission to this article for a test user. If i than logged in as test user, i could edit and publicate this article without any problem. I also got no message, that I has no access to this article.

http://wordpress.org/extend/plugins/wpnamedusers/