Don't really understand your question.

You signup using your email address eg yourname@yahoo.com. So any valid email address will do. Genesis will send a verification email to the email address that you use to sign up to confirm that it is you that actually sign up. A common practice for any website sign up procedure.

I encountered tis issue, just replace / with stroke word...that is what I did. Some ppl may not have issue if their address without /