Unfortunately, what can happen is that the steel tube is twisted/damaged when the sunroof frame needs to be removed from the car unless, of course, the 'frontscreen out' method is employed to remove the frame. In Michel's case, the steel tube was twisted and damaged to the extent that the steel cable would only move approximately two inches in either direction.
Therefore, it was not possible to refit the various components in order to close the roof. Luckily enough, I had saved a good replacement steel tube that we (Michel and I) were able to refit. This tube had to be routed through an opening in the 'C' pillar to connect to the sunroof motor/clutch which had to be dismantled in situ before the old, and damaged, steel tube could be removed. It took hours. Regards Styria