1. Some basic tools you may need. - A decent text editor. Notepad++ (free) will do the job for most things, but I strongly suggest you get a slightly more advanced editor like : Sublime text (free ), Vim or Atom . Most game files can be opened/edited with any of these tools. - An advanced image editor like Photoshop (free trial ), Gimp (free) , Pixlr or Paint.NET - 3D modelling programs : 3DS Max (free trial) , Maya , Poser , Blender (free ) , ... - Plugins for textures like .dds : Nvidia Texture tools , .dds Gimp Plugin, .tga/.dds thumbnail viewer,... - For specific tools for Cossacks 3 : check this thread. 2. The game files/scripts are written in the Pascal language. You can find some basic syntax tutorials here . 3. The game files can be found in your steam folder : C:\Program Files (x86)\Steam\steamapps\common\Cossacks 3\ . I strongly suggest you do not directly edit these. Instead take a copy of this folder and put it on your desktop. If you did manage to mess up your game, go to your steam app, select the Cossacks 3 game in your library and right click on it -> Select Properties -> Local Files -> Verify integrity of game cache. This should reset any modified files to their original state. 4. Trouble shooting: 4.1 Use editor.exe to initially test your mods. It will display logs with errors if any and which line number. From within the editor.exe you can play the game aswell. Press Control +T to test the map, and you will be in the Main menu, where you can select random map, load game, campaign. 4.2 Turn on logging. Find the cossacks.ini file in the main Cossacks 3 folder. and set LogFileEnabled to 'true' Code: section.begin GameSaveDirectoryPath=cossacks LogFileEnabled = true LogFileRoot = true LogFileName = cos section.end You can do the same for editor.ini Now you will find a /log/ folder with detailed logs in your main Cossacks 3 folder next time you start up the game. 4.3 Finding a specific error in a .inc/.script/.aix file: - start external editor, when the console window is up with the log ; right click on it - go to statemachine at the bottom, then select 'edit- modal', then," file - open" - select your file, you may have to select at the bottom 'all files' type - then go to "states" at top ; and hit compile It should tell you the error. 5. Using the modmanager. Once you have edited some files you can choose to use the modmanager to enable/disable your mod. You can find the modmanager.exe in the main Cossacks 3 folder. To make/add a new mod , start the modmanager.exe, click on the create button and give the mod a name (eg MyMod). Close the mod manager. Now you will find a new folder called 'MyMod' inside the Cossacks 3\mods\ folder. This is the folder where you should put your modified files. Note: use the same folder structure as the basegame. Eg. If you modified country.script, then create the parent folders for it in your mod directory : Cossacks 3\mods\MyMod\data\scripts\lib\country.script If the mod is enabled, the game should load the mod. 6. Some general hints & tips : - Know your game. It will come in handy to quicker understand the relation between file's and entries. You will also better understand the consequences of your changes. - Read a lot. You never have enough information. - Try out things. Don't be shy, you will learn more from your mistakes than anything else. - Don't copy & paste, but write your own entries. This will make you think and understand what you are doing. - Don't be shy to ask questions. It is not the questions that are silly but often the answers. We all have to learn everything. - Don't try to run before you can walk. Do small changes at the time and test often. This will help you to narrow down possible problems and errors. - Play some mods. See how other people have done things, what is possible,...It is a great learning school. - If you make your modifications with loving care and dedication, you are bound to succeed. - Work on a copy of your installation to avoid having to reinstall your game(s). - Back up your modifications frequently. Different drives, USB sticks, dvd & cd RW's, internet sites, cloud services, anything goes... - Do not publish too soon, but test properly and get feedback. - Above all, get organized. Clean up your desktop, it is your working space, you don't need those 999 shortcuts to everything anyway. Instead put your most frequent used programs in your taskbar. 7. More detailed guides and information https://www.cossacks3.com/forum/index.php?threads/modding-tools-guides.29024/ Got more hints, tips or good advice for beginning modders? A useful tool you can't mod without? Post below!