The Parts Bin Motor called “Motor_prop_medium spinner 1″ was accidentally put in the Parts Bin with its center of power set some distance away from the engine. When you use this motor, you may find controlling the model a bit unusual when it is under power.
After bringing this motor into your workspace, right click the motor (it will be red in object list) and select “Engine” from the context menu. Change the Center of Power to 0.0,0.0,0.0, or drag it to the center of the spinner.
We will fix this in the next version release.
Sunday Flyer Software