Read the detailed instructions on the list.txt file from the GitHub pull under Docs:  PlayVideo Installation.doc. It describes some options in more detail. After ripping more videos and placing them on the USB drive, update list.txt.  Use the volume levels to equalize the volumes of all the videos in your list. 

Once PlayVideo is running smoothly, there is no need to keep the keyboard or mouse connected. Note that you can add more USB drives if the first one is full. See the instructions for list.txt for addressing multiple USB drives. Sometimes when USB drives are moved around you have to boot and shutdown once to make the system "forget" the old USB drive location. When you shutdown, be patient. The Raspberry Pi green flashing light has to stop flashing. Then you know the shutdown is complete.