About Game Configurations
These configurations are the largest and most complex ones. A Game Configuration contains all the settings that determine Doom Builder's behavior when editing your map and optional features that are specific to certain map formats can be enabled or disabled here. A Game Configuration also keeps all information about hardcoded actions and things in the game, which Doom Builder cannot find in the WAD files. You can find the Game Configurations in "Configurations" directory, which is a subdirectory of your Doom Builder's program directory. Subdirectories are not searched by Doom Builder for configurations, but you can use them for include files.
Many settings in Doom Builder's user interface as bound to the available Game Configurations. This is because the user often wants to use different resources and compilers for a different project. When Doom Builder starts up and detects a new Game Configuration file, it will automatically create default settings for that configuration. The following default settings are read from the Game Configuration (only when first detected by Doom Builder): testparameters, testshortpaths, defaultsavecompiler, defaulttestcompiler, thingsfilters and texturesets.