Download it, extract it, open the folder 'Scenarios', cut, paste, take the game file (BIQ file) and paste it on its own in the scenarios folder, open it (it opens as the editor), press 'Alt-Enter', look for the box that says 'Scenario Search Folders', and type '..\scenarios\*****' (*****= name of mod folder). The mod is now ready to play. Start the game, click on the button that says 'Civ Content', click on the mod, and, finally, play to your heart's content.