Go to your WebControl System [http://yourdomainame.com/cgi-bin/plusmail].
Once logged in you would go to set-up scripts choose SiteBuilder (requires license). if SiteBuilder with your account you will not need a license
Enter a password and click set-up scripts. The password must be written down and remembered, you will be asked for it again during the registration process.
For registration of SiteBuilder you will have to wait 15 minuets after set-up and proceed to http://yourdomain.com/sitebuilder/register.mv
Once SiteBuilder is registered you can go to http://yourdomain.com/sitebuilder/builder.mv