When I close the driver side front window it goes to the top- then immediately lowers to the half way position. If I gently inch the window up it stays up. This problem started out of the blue and without warning. Any ideas?

Mine does this to. I found that when I put the window up, If I continue to hold the switch down for an extra 2-3 seconds it stays up.If I let it go as soon as it reaches the top, it comes back down as you mentioned.

Go all the way down and hold the switch for 20 secs. Then all the way up and hold it for 20 secs. That should reset the regulator.

Yup that is a way to calibrate it again, it is usually needed if a battery is disconnected for too long while the windows weren't fully closed, it lost its calibration.

Also happens if you live in cold climates and the windows freeze. Then they lose calibration.

Good point, that is a cause as well.