When I activate the hide backend feature and try to login I get a "Not Found. The requested document was not found on this server." error page.
I'm not sure what's going on. It worked prior to the plugin update. If I recall correctly before the update the plugin modified the htaccess file to hide the backend. I'm not seeing any such changes to the htaccess file after the update.
Perhaps it should be noted that my wp installation exists in a subdirectory. So right now I'm logging in via 'www.domain.com/sub/wp-admin'. Activating the hide backend feature and attempting to login via my chosen slug such as 'www.domain.com/sub/enter' produces the 'Not Found' error. It's doing something though because when it's activated it also causes wp-admin to produce that same error page.