On the left hand side of the application is a panel labeled “Files”. At the bottom of this panel ar two buttons labeled “Add File” and “Add Dir(s)”. Click the one of your choosing.
If you selected “Add Dir(s)”, you may be prompted with a warning about this being a time intensive process. Click “Okay”.
Wait as the files are added to the application. You can tell this process is occurring by the blinking green LED in the bottom right hand corner. When the process is complete, you will see your files appear in the left hand Files panel.