When you signed up (and paid) National TRF will have sent you a confirmation email, which includes your important TRF Membership Number. Check your spam folder if this doesn't ring a bell.
Don't delete this email as it's the only record of your membership number now they don't issue a membership card anymore. This email also explains how you can get access to the TRFs Green Roads Map (GRM) showing you where the legal unsurfaced routes are.
Last night I sent you a Welcome email from the Devon group, the email attachment includes the information you need to obtain the 'overlays' of the lanes from John Leah. Again check your spam folder.