2011 E class with the panorama roof - today after closing, the back part would no longer retract (just bunches up about 5cm then stops). Has anyone had issues with this? Seems that the back retractor is broken. - I am taking about the fabric, not the glass.

Haven't had a problem with it yet. Sounds like a trip to the dealer is in your future.

Pretty common problem and not a big deal to fix. Your dealer will take care of you!

What's the issue here? Is it the motor or that is simply gets jammed and needs cleaning or lubrication? Is the E-Class (212) the first model to get this style of sunshade? I know that is is on the revised C as well now.

The roller shades have been around since panos first came out (2003 E-Class era). I believe the issue is with the rails and how the pre-tensioner on the fabric shade interacts with them.