You may have seen these already, but in case not, there's a website which has a number of colour photos - apparently original, not colourised - taken by the French later in the war.
No vehicles except for a Renault truck, which may be grey, blue-grey or green beneath an ample covering of dust - it's guesswork. Nice reference material for Horizon Blue though.
There's also a colour photo of a large tent hangar.
Ha ha, love it! Looks like proper Old School Meccano too! I suspect those wires coming out of the roof go to the yellow control box on the left (you can see a bit of the wire looping round bottom right).
Another Meccano enthusiast, David Hobson, has also built a Meccano Mk I and an A7V (third and fourth rows on the following linked page)!
Glad you like it chaps, but I must ask if anyone looked at the colour photos, or you were distracted by the big boys' toys?
I was struck by how modern some of the scenes looked - they could have been photographed yesterday; it's not something you tend to see with colourised B&W images, and I think it makes the men and the war seem much more real than the distanced version we see in B&W.