Looks great, José and Roman!
I also use wood for my dio.
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And great looking concrete!
Hmm, "paper mixed in a blender" sounds good!
I also have to fill and cover some parts on my DIN A4-sized diorama later. (29,7cm x 21,0cm)
Possibly this can be a solution.
A long time I didn´t continued my both dioramas. (10cmK18 and the soviet venus lander)
But on the Atlantic-wall dio the last steps were (if I remember correcty
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) making another smaller version of a book and completing the wooden panels.
I don´t think, that I will use propaganda-posters on the scene.
But I will try to add some small parts on the wooden walls. (for tools and other things)
I didn´t bought any figures yet.
After a small research I found possible places, where the shown photo (published by Ace-models) was made.
At one of the few places on the channel-coast in france!
In a big pdf-file I found (possibly correct) information about types of defences along the A-wall for the documented places.
greetings...
Soeren