Excluding Computer or Plex Media Server and Xbox from VPN?

I have searched but have come up empty.

My setup is an asus n66u router flashed with Merlins build running Openvpn. I connect to the VPN through the router, so my whole network is secure.

Does anybody know how to exclude either my computers IP or the port for xbox live and the port for plex media server from going through the vpn?

Thanks for the help.