There are 2 ways to solve this problem.

1. Uninstall NF
2. Re-download the game client from here:
http://www.navyfield.com/down/game.asp?MenuDiv=3
3. Re-install using the newly downloaded client
4. Open NF and enyoy the new SN nation.

OR

1. Go to http://www.megaupload.com/?d=ON61A9GL
2. Download.
3. Unzip Files.
4. Copy and paste and overwrite .spr files in "SPR" folder.
Default location: C:\Program Files\SD EtherNet\NavyField\SPR
5. Open NF and enyoy the new SN nation.

I did number 2 and my NF runs fine.

MOD NOTE

Added info to existing thread and locked