How do I set up the domain to the Citadel Webcit web server?

I have a domain, mail.sturmkrieg.com, and I'm trying to set it as the domain that goes the Citadel web interface. How do I do this?

I set the ports in /etc/default/webcit to 2080 for http and 2443. The Citadel Webcit port says 504. How do I allow access to these with the firewall? I used the firewall directions here: [1].

Also, how do I setup MX records to the server?