If you created the ball and background in Motion you can just change their color. You could add a Invert filter which will allow you to change black to white visa versa. If you created the ball in a program such as PhotoShop just drag the new ball over the old one. Motion will create a hooked shaped arrow. Let go of the mouse and it will swap out the old clip for the new one, that way you don’t have to make any changes…if the two balls are the same size that is. Hope this helps.
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