(Here's a direct link in case you don't have Flash installed: Here is a video that shows the entire process of installing a custom campaign: Embed Removed: That is because all the data is referenced in relation to the folder structure, so ideally everything has to be inside the Starcraft II folders. However, a modfile must be inside the 'Starcraft II/Mods' folder, and if there are several maps which load automatically after one has ended (campaign), then they also must be placed inside the Maps folder as instructed. If it's just a mapfile, then you can place it anywhere on your computer.