First of all... a typo:
"If you leave it black, it will be disabled."
...should probably be:
"If you leave it blank, it will be disabled."
Also, if you have WordPress installed to a sub-directory, the description paragraphs indicate incorrect URLs.
It currently looks like:
Change the WordPress Login URL? http://domain.com/subdir/ ______________
...when it should be:
Change the WordPress Login URL? http://domain.com/ ______________
And, after logging in with this configuration, it redirects to http://domain.com/subdir/login (where "login" is my customized URL) instead of going to http://domain.com/subdir/wp-admin, and as a result, returns a 404.