Well the trick is that the ONE specific page https://dev.grc.com/users/sign_up is protected with old style HTTP Auth protection. It needs a specific hard coded userID and password, which Steve has requested stay only listed on the Newsgroup. (If you don't provide it, you will receive an error: 401 Authorization RequiredI guess I'll be waiting.
nginx )
So the ideal solution is to join the newsgroup, which is not always a trivial experience, but you can start that at https://www.grc.com/discussions.htm