What R0J0 said: http://www.eli0s.com/Tests/Trail.capx (right click and Save Link As)
Use the arrow keys to move the red ball.
Have in mind that this approach will produce a lot of sprites, play either with the fade out time or, as R0J0 said, use the on every x seconds condition to lessen the spawning frequency.
thanks a lot that's amazing i was stuking on it since 4 days
any way what you prefer
1- BALL DIRECTION MOVING + EVERY 0.05 or EVERY 0.05 + BALL DIRECTION MOVING (the 0.05 is below or above)