I have a mail VPS server and I'm installed PMG on another VPS to test it. I have a config like this:
PMG server: pmg.server.com (IP 5.5.5.5)
Default relay: mail.server.com (IP: 1.1.1.1)
Realydomain: mydomain.com
Trusted networks: Mail server IP (I think this is not mandatory)
I didn't change...