I have looked through the various help topics but can't find a quick answer to my question. Hopefully the forum will come to my rescue. I have a video of my golf swing; using Kinovea I have drawn 2 vertical lines to the side of my body, one left & one right; I want to see whether I "sway" forward or back as I swing down & thru the ball. I save the (using both options to merge and keep key images with the video), but when I then play the video my lines are there OK but fade away as I play the video. Any help appreciated. Thanks.
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