It may still be one of the switches. I don't know how they're wired in the punto, but in most cars, the passenger one piggy backs off the driver's master switch. That way, it is possible for one of the switches to fail and put the whole system out.
My guess would be the switch that is located on the driver's side has gone - this is normally used more often than the one for the passenger (ie when it's just the driver in the car, and he/she drops both windows for a bit of fresh air).
Try removing the switch panel in the driver's door, and temporarily plug the switch for the driver's wndow (which would be known as working if the driver's window still works) into the wiring for the passenger window, and try again. If that doesn't work, try plugging the working driver's window switch into the passenger switch for the passenger window (with the driver's switch for the passenger's window reconnected). If either way makes the window work, then you've found the dodgy switch
If you still have no joy, then there's something amiss with the wiring or motor - get the multi-meter out and check for voltage being supplied to the switches, and then any current being drawn (ie the motor is trying, but failing), or for continuity between the two wires that actually connect to the motor (no continuity at all means dodgy wiring from switch to motor, or motor really stuffed!)
