Euan,
Welcome to the COW Motion forum, it is great to have you hear.
To simplify the project I would get rid of your still grab. Place a “Hold Frame” behavior to the video so it freezes the movie until you want it to play. If you want the hold to ease into movement then use the “Set Speed” Behavior. These behaviors are in the retiming category. Hope this helps and best of luck.
Stephen Smith
Utah Video Productions
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