The document describes how to add interactivity to a Flash file by: 1. Adding ActionScript code to make buttons control playback and transition between photos on different frames. 2. Creating motion tween transitions that smoothly change the brightness of photos when changing frames. 3. Editing the code to make playback continue from each frame rather than stop. 4. Adding stop commands to end playback after each transition completes. 5. Animating a movie clip symbol to contain a pulsing animation played on button rollover.