The files "AnimationScript.py" and "Gearbox" are under GPL V2.0 License. Refer to "LICENSE" file for further info.
To animate the gearbox, open "Gearbox.fcstd" in FreeCAD and then make visible FreeCAD's python console and paste there the code of "AnimationScript.py". To stop the animation, type at the console: timer.stop()
It will run as a macro too, but then you will not be able to stop it.
Have fun!