Attached is a marked up version of the window schematic. At the passenger window motor there should be the following wires:
1. Large brown/red stripe - full time battery power
2. Red - enable signal from FEM
3. Red/blue stripe - global open signal from the FEM
4. White - window up signal when grounded
5. White/green stripe - window down signal when grounded

We don't have to worry about pins 1-3, since the window is functioning and works when global open/closing is used. (Side note: I'm not sure what signal comes from the global wire to the motor, it would have to be a variable signal that can command the motors to open or close as appropriate, completely different from the normal open/close switches).

Pins 4-5 are the manual open/close signals. The two signal wires from the passenger motor first go to the passenger window switch. Then they go through several connectors over to the driver's switch pack. They are white and white/green. If either of these wires is connected to ground, the motor then runs up or down as called for.

To sort of get our bearings and see what's going on, can you pull out your driver's switch pack, unplug the connector DT4 (20 pins) from it. Connect a jumper wire to a good ground. When you touch the ground lead to the switch pack connector pin 11 (wire white/green), the passenger window should go down. When you touch the ground lead to pin 12 (wire white), the passenger window should go up.

Another question: the symptom of the window going down from the driver switch: does the window first go up a couple mm, then reverse and go down? Or does it only go down?