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The best way to install and use the mod is by utilizing Cerus Vi's Mod Manager. However, this document is to teach you how to use the manual file swapping method.
Save the SupCom2_0_1_3_v111.rar file to your hard drive; it does not matter where, but the most convenient spot to save it would be in your "Supreme Commander 2" Steam folder, since we need to work there anyways. This varies depending on where your Steam in installed, but by default it is located at C:\Program Files\Steam\SteamApps\common\supreme commander 2\ on many operating systems (if you have trouble finding it use your Operating System's Search Function and look for 'supreme commander'). This is a good spot to put the SupCom2_0_1_3_v111.rar file for now.
While you are in your Supreme Commander 2 Steam folder, there is a subfolder called \gamedata\ in that same folder, inside are 2 files; lua.scd and z_lua_dlc1.scd which need to be moved or renamed so as not to end in .scd. Either take these files and store them up one folder in your \supreme commander 2\ folder, or rename them to lua.bak and z_lua_dlc1.bak respectively (as long as they do not end in .scd). Delete any other mods (or previous versions of SupCom2013) you have installed. They will most likely not be compatable with 2013 mod.
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Now, go back and open the SupCom2_0_1_3_v111.rar file with WinRAR or WinZip.
Inside will be 3 files; installation instructions, a guide, and a file called SupCom2013v11_for_Mod_Manager.scd which is the one you are looking for.
Using WinRAR/WinZip, extract SupCom2013v111_for_Mod_Manager.scd into your \supreme commander 2\ folder, (or somewhere else easy to access on your hard drive). Go to where you extracted the file and rename it from SupCom2013v111_for_Mod_Manager.scd to SupCom2013v111_for_Mod_Manager.zip so that you can open it with WinRAR/WinZip (or right click on the file and hit 'Open With' and select WinRAR or WinZip).
Once inside you will see 7 files. Take all of these files, and put them into your \gamedata\ folder (though really only the 5 .scd files are important). If asked to Overwrite any files, be sure you have followed the back-up procedure of your lua.scd and z_lua_dlc1.scd files (as described above) before destroying any of your local game files.
Restart your Supreme Commander 2 game, ensure that you have the DLC enabled, and you are now ready to play the mod. Either hook up with your mod enabled friends online (you will cause DeSync errors if trying to play with non-modded players), or play a skirmish versus the A.I. Don't have friends yet? No problem! Join the Steam Group, or find us on our TeamSpeak3 server.
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Save the file downloaded from the internet. Open it with WinRAR/WinZip and then extract the .scd file inside and open that file with WinRAR/WinZip. Find your SupCom2 \gamedata\ folder located in your Steam directory. Extract all the files (there should be 7) from the second file that you opened into your \gamedata\ folder, being careful not to overwrite any of your local game files without backing them up first (lua.scd and z_lua_dlc1.scd that are in your \gamedata\ folder both need to be backed up before overwriting). Restart SupCom2, enable DLC on the main menu, enjoy!
To uninstall and go back to 'Vanilla' SupCom2:
Go back into your \gamedata\ folder. Delete the following 5 files: _Mithysmodsupport_v7.scd, SupCom2013v111_Adds.scd, SupCom2013v111_Merge.scd, lua.scd, z_lua_dlc1.scd.
Replace/rename (depending on if you moved them or renamed them) your original lua.scd and z_lua_dlc1.scd files back where they belong in your \gamedata\ folder. Restart your SupCom2. If your game does not function properly, right click your game in your Steam Library, select properties, and in the 'Local Files' tab click on 'Verify Game Cache'. This will check your copy of the game for any missing files, however if you failed to delete any mod files this function does not scan for extra files so you may still get errors if you did not delete the 5 mod files properly. Delete the 5 files listed above and re-verify your game's cache again through Steam.
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How SupCom2 Mods work:
At different times throughout the game different files are called from the \gamedata\ folder, interpreted by the game itself, and you see the results on your screen. By adding and replacing files in your \gamedata\ folder you are giving the game different instructions to run than what was shipped with the original game. While it is sometimes possible to add new files, or merge certain data into the game non-destructively, but in other instances the engine looks in specific places for some files that the 2013 Mod Team wanted to modify, meaning you have to overwrite some of the files in your \gamedata\. This means you need to back up any local game files before you overwrite them with mod files so that you can go back to the original game when you are done with the mod. The game only looks into files that end in .scd (or searches through sub-folders named .scd for files of the same type), so as long as you move your original files up one folder level, or rename them from .scd, the game will not read them. However if you maintain the .scd ending, or put them into a subfolder, they will still be read, and cause errors while trying to play the mod.
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