Sky router blocking site, how do i resolve

Hi

Sky broadband appears to be blockng access to a site i need to access,

How do i resolve this with them? or what other methods can i use to be able to access the site

Would a vpn work to get around this

The url is

http://member.registercompass.com/signup/

Can anyone on skybroadband tell me if they are getting the same problem also

Thanks