Bob -I had mine fail a week after buying the car (had 30m on it then) Dealer fixed the problem with new guides. I watched the install for a short while though and saw that the headliner was taken out before they started the work.
Have now around 135m on car and the tilt has given me problems as follow. Tilt the window up it will come back down on command-will not function though when called upon to slide back. If I get out of the car though when it's in tilt position and make sure with one hand that the window is coming back down flush as it should I can then make the glass slide back the way it should. If it gets caught in a bind coming back from the tilt position it will only go back to tilt and not slide back. Since finding this around 40m ago I try to make sure I don't tilt the sucker anymore just slide er back.
Hope that works for you too
Poolman