From Castle Wiki

Drag is an interactive behavior which causes the blueprint's actors to be draggable when touched.

You can add Drag by opening the Inspector for a blueprint, navigating to the Movement tab, and pressing Add physics or controls. Make sure the blueprint already has Dynamic motion.

Using Drag with Rules

  • Drag adds Triggers for When a drag starts on this and When a drag stops on this.
  • Drag can be enabled or disabled during play time using the Enable/Disable behavior Responses.