Bumping this thread whose last reply was almost 6 years ago JUST to confirm that I had the pano sunroof binding issue and the rear glass was stuck in the “up” position. I slid the rear “ramps” back to lower the rear glass, performed the plastic tab surgery outlined above, gave all the tracks a good clean and re-lube with lithium grease and IT WORKS!! Thanks to everyone who posted info above- SUPER HELPFUL, even this far into the future.

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2004 X5 4.4i