You can either use 0.0.0.0 as IP andress and Mask to allow everyone, but this will open the server-manager.
If you only want to open /user-manager, you should create a custom template for /etc/e-smith/templates/etc/httpd/conf/httpd.conf/VirtualHosts/27ManagerProxyPass and edit the first part like this:
    foreach $place ('server-common','user-password')
    {   
        if (($port eq "80") && ($haveSSL eq 'yes') && ($plainTextAccess ne 'yes'))
        {   
            $OUT .= "    RewriteRule ^/$place(/.*|\$)    https://%{HTTP_HOST}/$place\$1 [L,R]\n";
        } else {
            $OUT .= "    ProxyPass /$place http://127.0.0.1:${'httpd-admin'}{TCPPort}/$place\n";
            $OUT .= "    ProxyPassReverse /$place http://127.0.0.1:${'httpd-admin'}{TCPPort}/$place\n";
        }
        $OUT .= "    <Location /$place>\n";
        $OUT .= "        order deny,allow\n";
        $OUT .= "        deny from all\n";
        $OUT .= "        allow from all\n";
        $OUT .= "    </Location>\n";
    }