ᐅ Okal house built in 2001 – how to open the roller shutter box

My crank-operated roller shutter is stuck and had to be moved manually a few days ago; now it’s completely jammed!

The shutter box cover doesn’t show any obvious way to open it as far as I can see.
Our house is an Okal Haus Ambiente Contura C 82, built in 2001.

Unfortunately, I have no idea how to open the roller shutter box. In the attached picture, you can see the crank mounted underneath the box.
The panel is fixed upwards with five screws and fits into a plastic corner piece at the top front of the window frame.

The covering board is wallpapered and extends up to the ceiling (you can see the edges of the board on the left and right). The wooden ceiling was added later during construction.

Maybe someone has had the same problem and knows how to open the box without causing damage.

Many thanks and best regards from the Heidelberg Neckar region,
Oliver

P.S. I’m new to the forum and thank everyone who keeps it alive.

Hi first of all, you need to loosen the screw along with the crank first. Then you should be able to pull the large flap towards you. CAUTION!!!
There could still be screws behind the wallpaper. It’s best to use a strong magnet to scan the area.

Thanks for the reply.
I will try as soon as the weather improves; we have 40cm (16 inches) of snow and it’s freezing cold here.

Best regards, Oliver

And it looks like the crank gear mechanism is slowly giving up.