Thank you for your message.
Do you mean that you've tried configuring access through proxy in the Host Settings
In case if you haven't done this yet, please try configuring access through proxy server as described in this tutorial
and see if this work for you.
In addition, please note that in case if you want to utilize RU Server, then RU Server only uses a single TCP port 5655 to communicate with Hosts and Viewers. Alternatively, when using RU Server as your relay server, you can specify your custom port values. For more information on ports used by RU Server please see this page
Hope that helps.