"Hello Michael and others, one question is left: how would you alter the example Michael kindly provided to have two start/stop buttons, ..."

"hello Michael, many thanks for your help and the attached example which does exactly what I had in mind. Best regards, Hans"

"Hello everybody,   I try to set up the following on an informational slide: The rotation of an image object can be started and stopped..."

"Thank you both, I'll try following your suggestions."

"Hello, my task is the following: 1. show the user a video with a two-dimensional rotating object. 2. Ask him in which position (angle)..."