This will help you upgrade the game to latest version from wz2100.net
Download the latest version
Goto https://wz2100.net and download the either the traditional installer or the portable version
The difference between installers:
User data such as savegame, screenshots(not taken by Steam) and mods are located in %appdata%\Warzone 2100 Project\Warzone 2100
User data such as savegame, screenshots(not taken by Steam) and mods are located in Steam\steamapps\common\Warzone 2100\Warzone 2100
Open the folder where the Steam version is located.
- Find the game in your Steam client and click the ‘cog -> Manage -> Browse local files’
- Select everything in the folder and delete them (this is to avoid problems between the Steam version and the ‘proper’ version)
- Now open warzone2100_win_x64_installer.exe or warzone2100_win_x64_portable.exe that you downloaded earlier.
When you get to where you want install the game, change the path to the (now empty) Steam version (located in Steam\steamapps\common\Warzone 2100)
- When the installation is complete, find the game in your Steam client and click the ‘cog -> Properties…’ and disable ‘Enable Steam Overlay while in-game’.
This is to avoid graphical corruption in the game.