The Motio tool uses the assumption of brightness consistency of an image to generate motion vectors from one frame to the next. That is, the luminance values remain constant over time, but their 2D position in the image may change. Flashing lights, shadows, and other image changes that violate brightness consistency may interfere with the generation of motion vectors and cause problems with your retiming operation. You may want to first fix these problems using a Paint tool or CC Basics tool for example, then calculate the adjusted forward and backward motion vectors with a Motio node. Once this is done, you can connect the adjusted vectors to a Retimer tool and use your original image as the input.