me and a couple friends found a couple of bugs about the stride add-on
if you walk on other people, black footprints appear in the air
footprints appear on ledges, making them stick out from the top of a wall
in vehicles, going upside down also creates black footprints in the air
there's only one shape of footprint, so people with the other leg have foot-shaped footprints
also I'm quite sad that you can't save the materials you've binded, the ones created by /setfootprint