Dag nab it, Kabar you're too good and right about every point.
They are screen shots I took while playing the game as England. The shots where the environment is really bright green and almost tropical---I think I was fighting either the French or the Dutch in either French or Dutch Guiana.
Unfortunately, Empire total war is such huge game (12 gig foot print on my hard drive) that the developer just couldn't include all the variations of uniforms, or even have the artillery painted in the correct colors for each nation.
Actually the Duchy of Württemberg (part of Germany) used natural wood during the Napoleonic period. Consequently all the artillery--no matter what nation is pretty homogeneous as are many of the uniforms.
The game covers the all of18th century, but the artillery doesn't change that much in the game. One starts with heavy fixed direct fire cannons, but as technology develops you get movable foot artillery and then fast horse artillery finally obtaining canister and then shrapnel, then howitzers get added-----first 12 pdrs and then 24 pdrs. (Of course most nations used bore diameter to categorize howitzers).
With the howitzers one gets various types of exploding shells. Next come heavy mortars and even Congreve rockets. They've even got a fantasy item--the Puckle gun. It's a rapid fire revolving cylinder cannon. It really did exist, but was never used in any warfare.
I know there are a lot of inaccuracies, but where else can one get to fire cannons all day long and blow up all the little virtual structures and soldiers they want---and never have to leave the house.
Cheers