I'm having similar problems. I used the wizard to create my pages, let the behavior create the DB table and the security pages and and it works, sort of. It automatically requires a username longer than four which is ridiculous, it sets password strength much greater than I want and adds a security question which I don't wan and don't know how to remove.
How do I require the first and last name but without length?
How do I set the password strength?
How do I remove the security question but leave the captcha?