This one is a fairly standard picture of the 28x22 wood/cork board that shows up online:
This is a 200 DPI board for printing:
Here's another look at the wood/cork board with the original for comparison:
There's two problems I see with this iconic wood and cork German HQ board. One, it doesn't fold, and it's freakin' huge. This one at least does not appear to be made of two or four pieces, to aid with storage—others were, which as I said was part of the impetus for doubling the corridors in the first place.
The second problem is a personal/aesthetic one that I hope would be taken as constructive criticism if it were being posted for the first time today. I've been watching a LOT of videos on making and painting terrain lately for inspiration for my own project. Probably this one predates YouTube, actually, but I would suggest that the homebrew board looks great, but … flat. The tiles look like they have a coat of paint on them. Looks like they started with a black base coat and then painted over that with acrylic craft paints. Which is fine—it's how I'd do it at least! But if they made a couple of washes, a black and a brown (depending on the room), it'd tone down those colors a lot and darken the board substantially. Now, a major complaint I have of terrain crafting channels is that their stuff always looks to me like fifty shades of black on camera, but that's in large part because they start with gray and brown. You've got primary colors here, but don't be afraid to make it darker than you think it should be. I'd go back then and paint highlights with a very light dry brushing of … I think you'd need three colors. a light tan or khaki, a very pale blue, and an ivory or bone white.
Corridors would get the khaki. The central gray room would get the blue, and the green as well (very lightly for the green!) I'd go back and hit the faded yellow rooms with the white, and the green room again (again lightly, but this one will be easier to see what to do to taste…) The others would get the khaki. If you want to do the kind of streak across the central room, do that in khaki as well, and maybe dust some of the white where it seems to want to be all over.
And then we just put a happy little orc right there. He's just gonna stand there, he won't hurt anybody.
Growmrrrrrghhggghhh… Stupid elf-thing…
ETA: Maybe some of the white in the blue rooms would be in order.