The form on the keymaster tab is for an free Keymaster account.
You looking to sign up as a user?
Just go to the ForumLines site at which you want to sign up as User and click the Sign up link near the top of the page.
A Keymaster account allows you to create a ForumLines site. Please use a valid email address, cause a email with a link to activate your account will be send to this email address. Problems? Add a post on the Support forum.