The update for this was very overdue, apologies but I'm extremely lazy. Luckily the guys over at https://www.hard-light.net/ have made things a lot easier than it was previously. Note, this is for running the game through Knossos, unless you want to run the original Freespace 2 through steam, it's far better to run the game through the Knossos client.

Now to get the Freespace Open running you can use the below section.
1. Download Freespace 2 via Steam
2. Go to https://fsnebula.org/knossos/ , run the program and designate the directory you wish for all the new data to be saved.
3. Open the options in Knossos using the cog in the top right of the window and select the correct resolution for your monitor, click save then select retail FS2 the from the home tab.

If you wish to use the updated textures or play the various mods/ campaigns for this game keep reading.
4. From the explore tab of the program, for the updated textures, select "Freespace Upgrade Media VPs", alternatively select the mod/ campaign you wish to play, click the install button.
5. Return to the home tab then click play on the mod you wish to play. Done!


Now finally for multiplayer!
6. Go to https://pxo.nottheeye.com/ and register, then open the verification email sent and confirm your account.
7. Launch the game, and select a multiplayer character.
8. Press F2 to bring up options, then click the multi tab.
9. Tick the PXO button in the bottom left, then enter the login and password shown on the "Game Credentials" section of your account.
10. Click accept and open the center hangar door.

Currently there are mods to play the campaign in Multiplayer, however note that you will need to boot the game through the multiplayer mod in the menu to have these appear in the multiplayer campaign sections.

All done, that should cover everything.

Once again thanks to everyone over at https://www.hard-light.net, they're the ones who've done all the hard work! Go over and saying hi/ thank you for their hard work.
There is also a Discord for Hard Light Productions, you can join at using the following link.
https://discord.gg/R9TvRFRyUm

Good Luck, Have Fun!

Last Updated: 12/09/2021