I discovered the solution. I was working in a DV 16×9 project (720X576 1,422 pixel asp.). The motion thing only seems to work correctly in a square pixel project…… When I did the same thing in a 1024X576 1,0 pixel asp. it all worked well…. What unfortunaly didn’t work was making a new project with the square pixel and importing the old project. I needed to redo the compleet editing from the source, thanks to adobe.