Flow sliding roof clogged

One of the four processes on my sunroof was clogged.
At the start of the Audi after a rain shower, about 1 half litre of water came down from above to the seat. In addition, the panel was immediately wet at the side bars from the front to the back. Also on the grabs above.
After drying, ugly water stains remained that look like lime stains and can hardly be removed.
Even on the hat rack a white water edge appeared.
Since it was rainwater, it can actually contain no lime. I have already tried chlorine bleach (against lime) and a brush, but that also hardly makes any use, even if it has shown the best effect so far.
Does anyone here know good advice?
If not to be relegated:
Removing the panels shouldn't be so easy as Air-Bag in it and unscrew the hat rack??