When this plugin is activated on a WP install that is in a subdirectory (like /wordpress), you cannot get to the login screen by going to http://site-name.com/wp-admin, but rather you have to go to http://site-name.com/wordpress/wp-admin.
This isn't an issue for me, but it is confusing to tell my clients that for now, your login URL is http://site-name.com/wordpress/wp-admin, but then after we launch you can shorten it to http://site-name.com/wp-admin.
I sometimes provide a link on the coming soon page to make it easy, but then my documentation & examples I provide to clients isn't consistent or reusable. It would just be much easier if /wp-admin would just redirect as it should.
Let me know if you need any more info. Thanks!