Config Files
Dark Messiah holds many of the settings you select in the in-game options - along with a range of other custom variables - in a file called config.cfg, which can be found in your \Program Files\Ubisoft\Dark Messiah of Might and Magic\mm\cfg directory, or under \Program Files\Valve\Steam\SteamApps\[Username]\dark messiah might and magic single player\mm\cfg for those playing via Steam. This file can be opened and edited using any text editor, such as the Windows Wordpad. The config.cfg file is very important, so you should first create a backup of it before you edit it or apply any other advanced tweaks.
While you can add, edit and remove commands directly in config.cfg, it is recommended that instead you create an entirely new file for adding custom commands. To do this, in the same directory as config.cfg, right-click in an empty area and select New>Text Document. Rename this new text document to autoexec.cfg (not autoexec.cfg.txt), and you can now insert all your custom commands into this config file. By default the Source engine looks for autoexec.cfg at startup, and if it finds it, it will automatically load and execute all the valid commands. Importantly: In Dark Messiah the engine appears not to automatically execute autoexec.cfg in singleplayer mode, so you must add the line +exec autoexec.cfg to your DMOMM launch icon - see further below for more details.
For multiplayer, an autoexec.cfg file will be detected automatically, but must be inserted under the \Program Files\Valve\Steam\SteamApps\[Username]\dark messiah might and magic multiplayer\cfg\ directory.