Line motion path

Without seeing the file, here are a few thoughts:

• Selected state is a toggle button so you have to account for selected and not selected states. 
• Here's what I'd do:
  • Assuming the animation starts automatically
  • Create a button that is starting state disabled when slide starts
  • Move object on motion path
  • Change the state of the button to normal when animation completes
  • Move object on motion path when user clicks button
  • Change state of button to disabled when user clicks button
• The animation will always restart when the user clicks the button
• With the button disabled, they can't click it in the middle and make it jump (unless you want that)