To add download a mastered version of a song from your File Library first log into your eMastered account, and navigate to the "My Library," section from the top-right menu.

From here click on the track you wish to master, and then click on the downward facing arrow to the right of the screen. This button will be located in the "options," section of the "My Tracks," area.

From here click the file type you'd like to download, and the download process will occur automatically.