Useless Machine geared motor
Torque increases proportional with current.  Thus dropping voltage , lowers available current, and torque.

Max Torque = 2000gm-cm @6V.
Stall current @5V=650mA

5cm -60gm lid uses 15% of max torque. Thus reduced speed is possible from 100RPM no-load to 30RPM but may require calibration or trial and error to set voltage.

The easiest way to set constant voltage is with an LDO regulator, which has very low dropout if you need most of the battery voltage or use the LDO with contant current to get constant torque. 

But To reverse the motor, a differential or H bridge is needed instead.

To do a whole sequence of random events, you need an embedded micro.

Switch requires a long throw solenoid to be pulsed on.