that could work - thank you ill let you knowHmmm. I suppose there are any number of ways to make a door slide back-and-forth in a track. The tricky part is how do you do it in such a way that if someone gets stuck in the door it doesn't kill them. My first thought is to use a motor attached to a cam (or maybe a spool of rope?) attached to the door. When activated the motor would turn on and pull the door open. When the motor was turned off a spring or bungee cords would then pull the door closed. This way if someone got stuck in the door they could just push back agains the spring and it would open.