Do I turn the screw clockwise or counterclockwise to make the sensor less sensitive?????
I don't have one of these but, try one way then the other. Look at D0 with a voltmeter while you are doing this so you'll know when it toggles. (probably a 10 turn POT)
How do I know when I have reached the screws limit??
You will hear a tick like sound each time you make a full revolution when you are at an end of travel.
Can I damage it by turning too much???
How do I know, can I use a multimeter on the soldier bumps on back to see it change???
Measure the resistance between the center POT solder pad and one of the outside pads. (with the power off)