Is there any noise from the motor (assuming it's electric) when you try and operate the window, or is it dead? (pointing to wiring as you say).
As I have it up, I'm now reluctant to open it again until sorted, but I couldn't hear the motor running, (however, I had SWMBO aboard!).

Okay, I'll take a punt on this though Not sure if this will help, but I had similar problem on the rear window of my Beemer.
If it's the same mechanism (runner and cable) it could be a similar fault.
Okay, so the cable has a ball pin moulded to it and the runner has a socket which the ball pin locates into. If the ball pin comes out of the socket it can fall either side of it i.e: if the ball pin comes out and lodges itself
above the socket it will push the window down when operated but not back up (as the ball comes up on the cable but doesn't bring the socket/window with it therefore leaving it at the bottom, OR if the ball pin falls
under the socket when you operate the window the window will stay where it is until you manually push it down with your hands, but the cable will pull the runner/window back up as the pin is below the socket forcing it up.
The pin needs to be popped back into the socket, job done (unfortunately it's a door card off job

)
I know that was a long winded explanation and probably not easy to understand but it's a difficult one to explain without a diagram-so I'll post one below...
As I say this happened on my BMW and it might be a totally unrelated answer. If you can't hear the motor running it'll no doubt be electrical...so ignore the above statement

Not an Omega mech. but it'll give you an idea.
