Managing layers (send to front, send to back)

When you add objects to the surface, they are automatically added to the top layer of the drawing.  Each object you add to the surface adds a new layer.  Objects essentially "stack" on top of each other.  From time to time, you may need to access an object that is "underneath" another object.  The "Send to Front" and "Send to Back" buttons on the bottom toolbar allow you to move the highlighted objects.  In the example video, a rectangle object is placed on the surface "above" the action lines - the Send to Back button then pushes the object behind the action lines, allowing access to the action lines.  The Send to Front button brings the rectangle back to the top layer.