Junior class troubleshooting problems

Again, list the meter, settings, how leads are connected, and your reasoning for your solution.

Scenario 1:

A homeowner is renovating and upstairs room.  The room used to be a kitchen but the homeowner wants to convert it into a bedroom.  The homeowner wishes to remove a light and single pole switch that controls the light but is unsure where the circuit feed originates. This switch does turn the ceiling light on and off.   Upon arriving, you turn the switch OFF and remove the light from its ceiling box.  There is a 14/2 NM cable in the ceiling box.  You carefully remove the single pole switch and again, there is only a 14/2 NM cable in the switch box.  How could you verify the black wire at the switch is the same black wire at the light ?  Once you proved this wire IS the same, how is it possible that this light/switch works ?  What Code violation makes this circuit possible ?

Scenario 2:

A customer calls to complain about a faulty UP DOWN OFF switch that controls a commercial grade garage door opener.  There are 2 limit switches installed, one that stops the door motor at the top of the opening and one that stops the door motor when it hits the concrete fully closed.  There is no memory; the operator UP or DOWN must be held closed.  The complaint is this:  The upper limit switch stops the door when it is fully open but the door motor shuts off just seconds after the door is closed, meaning, each time the door is closed, someone needs to reset the OL relay on the magnetic motor starter.  What is the first thing you check ?  What is one possible cause of the problem ?