Add Files
If you wish to add a media file or a selection of media files into your Mezzmo library, use the Insert / Add Files menu item or Add To Library → Add Files toolbar button.
The Add Files dialog lets you navigate to the folder containing the files you wish to add. You can select an individual file or a series of files.
Tip: To select more than one file, hold down the CTRL key or SHIFT key when clicking on files.