Hello and here is a tutorial for Hmachi:
1. First off you need Hamachi which you can get here: Hamachi.en.softonic.com
2. Now install Hamachi.
(Hamachi is a free tunneling program that allows you to make local games public.)
3. Once Hamachi is installed you will get a little program that opens and says LogMeIn Hamachi. If the little power button is not on click it.
4. Once Hamachi is on it should give you the option to set your Hamachi name which can be anything.
5. Now to Connect to a network go to the little Network tab and click Join an existing network.
6. A window will appear saying Network Name and Password. Use one of the ones above.
7. Now once you are in a Network you will see the names of the others in it. Next to them is their IP which is before the /.
8. Right click to either ping them chat with them and do a few other things.
9. Now if they have a game hosted you can join them by going into Homeworld 2 on the HHF mod. Once the mod is loaded go to multiplayer and you can either create a game or host one.
10. Now to join a game you must click join and a screen that says enter IP will appear. Take their IP from step 7 and type it in. Once it is typed in try to join their game. If it does not work you either have their IP typed wrong, or you have different versions of the mod and/or game.
*This post was edited 6/16/2012 due to a hamachi update that limited the number of players in the same room to 5.