... This was a simple stand alone experiment. Hope this helps. All the best, Brian Nicholls. posted: 28 Mar 2012 08:41 from: Alan Turner I've just constructed the track as above and the dummy vehicle follows the control template- as it should. Is the slew Mode 1 or 2? I used mode 1 regards Alan posted: 28 Mar 2012 14:43 from: Martin Wynne Hi Brian, Thanks for posting your file. I have deleted my previous drivel because I have now reproduced your screenshot: 2_280931_290000000.png It's very simple -- what you have done is to move the dummy vehicle so far to the left that it has gone round a complete circle at the first radius anticlockwise, and reappeared at the top of the screen. I think if you had noticed the dimension in the mouse action panel showing a large negative position for the dummy vehicle you would have realised what was happening (ringed yellow above). The problem recurred on the test slewed template because when you change to a different control template, Templot doesn't reset ...