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Seriously folks. Buy the game and install it with GOG installer. Take the duke3d.grp file and put it another folder of your choice. Download eduke32 and put it in the same folder. Get he HRP file and put it in a subfolder called auto load. Start eduke32 and select the autoload folder as an option. Play the game. It is fantastic and you don't need DOSBOX. You can even delete your GOG files if you want.