In the screenshot section...

[Seign Thelas]

Where did the full 3D images on the first page come from?

[R'as al Ghul]

Which first page?
If you mean the screens at totalwar.com then I suppose you mean the shot of the Khan in his tent? That's from the intro movie for Mongol Invasion.

R'as

[Seign Thelas]

No. These:

http://www.totalwar.org/screenshots.shtml

The last one in the 3rd row, the first in the second row, and the first in the third row.

[Togakure]

You mean the third one in the first row, right?

I've played Shogun from the beginning and have never seen these images before. Maybe from the original opening movie, which I've forgotten. I gave my original game to a friend when I obtained WE-MI.

I barely recognize one of the building choices in the campaign map picture--the original icon for a port.

At first I thought maybe the shots were from the original trailer (https://www.youtube.com/watch?v=UZA-gqJL9Is), but they're not, from what I can tell. A mystery to me ....

[R'as al Ghul]

Looks like concept art to me.
I'm certain that those images are not in any trailer and I must admit that I haven't seen them yet or I don't remember.

R'as

[Noir]

The close ups are certainly not from any trailer; they might be from very early versions of the 3D engine (RTW engine). If you have played the historical campaigns in MI you'll notice in the Nobunaga one that he is depicted as a cavalry man holding a torch in the night; essentially the animation is that of the RTW:BI cavalry man in night battle that was introduced in-game 4 years later.

Generally speaking CA has always used the "next generation" graphic/engine in the intros of the game they have released ever since MTW. In the MTW intro you can see the RTW siege towers with a single man climbing the ladder. Also an early Rome vs Gaul trailer of RTW contained quite some of the "advanced" M2TW fight animations.

Noir

[Martok]

Those aren't screenshots from the RNJ mod that were somehow posted in the wrong place, are they?