Just a note on MultiPlayer.
If you're not a HyperLobbie person, and want to host, obviously you need to open port 21000 to your Router/Firewall/PC if you want to be a server.
Another tip, Magnum and I tested a Dynamic DNS client today, and you can type in DNS names instead of IP addresses in the join screen. So instead of typing an IP and port;
200.100.50.25:21000
You can type;
mypc.dyndns.org:21000
The host just starts a free dynamic DNS client beforehand or have a Firewall/Router that supports Dynamic DNS directly. You can read up on Dynamic DNS here;
http://www.dyndns.com/services/dns/dyndns/