I don't want to pop anybody's bubble, but two of the deisel boat I served on had the 2" X 2" strip, teak decks. The wood was coverd with black, preservative paint. You couldn't see the wood at all.
My other boat had steel decks. From farther than a couple of feet, you couldn't tell the difference in the material. And bare wood was never visiable.
I would expect that the Germans did the same thing, to avoid rot and warping.
So, unless you're taking atistic license, and showing a bare wood deck, I wouldn't worry about it.
As for deck tread (anti-skid) colors, the US Navy uses deck grey and black, are the4 only colors that I know of. As for civilian ships, they seem to have it available in almost any color you might want.
On my first destroyer, it took two guys to put down deck tread. One would put down a heavy coat of paint. Then the second would sprinkle sand on it, and the first guy would put a light final coat over that.
The last time I saw deck tread, being applied (on a surface ship), it came in sticky back, oval patches. You just peeled off the back and stuck it to the deck, whereever you wanted it. It was a lot faster and easier than the old way, but I don't know how it'd hold up on a North Atlantic run.
The anti-skid on subs came premixed, in 5 gallon cans.
For 1:72 and smaller, flat paints should do it. For 1:48 and larger, I'm not sure, 'still playing around with it.
I don't suffer from ulcers, I'm a carrier.