Since I do not use mouse movement, I do not know if there is a way to abort moving once you click somewhere. Is there? The few times I used it I wandered near a trap due to the pathing of mousewalk, and tried to abort by pressing the movement keys. That made my character continue walking along as mousewalk had planned and then to make the movements it had in cue from my keypresses. It killed me. I have not tried mousewalk since then.