Click the green car just once to move it. Double-click the red car to move it. The secret is the speed of the double click. It must be quick, under half a second. Longer than a half second gap between the two clicks is not a the double click but two clicks. Can you see how this is done in the code? Can you find a use for this 'trick'?
Use an invisible sprite to place the speech balloon where you want it. I want the green car driver to say something, so I place an invisible sprite near the green car driver and code it to say the words in a speech balloon!
