6.0 and later firmware:
The CloudTrax walled garden can support wildcards (i.e *.open-mesh.com) as of 6.0 firmware.
Domains in the format "facebook.com" will be wildcarded: all subdomains of facebook.com will be available.
Using the format "dev.facebook.com" will only allow access to dev.facebook.com and no other subdomains (www.facebook.com, etc.).
If you are using pre-6.0 firmware, wildcard domains are not supported. To allow access to specific websites for un-authenticated users, you'll need to list each domain or subdomain individually.