Subdomain blog for BuddyPress not Working

I have Wordpress Multi-Site latest install, BuddyPress and a SubDomain.

I had BuddyPress in blog (1) a while ago and I am trying to use a subdomain (7)

I have in wp-config.php

define( 'MULTISITE', true );
define( 'SUBDOMAIN_INSTALL', true );
$base = '/';
define( 'DOMAIN_CURRENT_SITE', '' );
define( 'PATH_CURRENT_SITE', '/' );
define( 'SITE_ID_CURRENT_SITE', 1 );
define( 'BLOG_ID_CURRENT_SITE', 1 );

I have in the bb-config.php

$bb->uri = '
$bb->name = ' Forums';
$bb->wordpress_mu_primary_blog_id = 1;
define ( 'BP_ROOT_BLOG', 7 );

If you visit and try to register it navigates to the root blog to register and gives a 404 page.

I want the site supporters area in a subdomain with groups forums etc:

Any help most welcomed!