@Grodny the Verdun version (which doesn't seem to be on Steam) is substantially better. It's pretty much the exact same map and layout with Industrial Age units and a World War I story line that moves a bit more smoothly.

The story of this makes no sense

To load the game itself.
Install the game
Press play
A window opens and just press play again.

To play the scenario there are two ways.

First Way - Note that I and my brother experienced no problem using this method unlike witht he second method
1) Click solo game
2) Load a scenario
3) Press the back folder button until you get to the the steamapps folder
4) Open the workshop folder
5) Open the content folder
6) Open the 287450 folder
7) Open the 830021154 folder
8) Open the scenario folder
9) Double click the World War III- Siege of Warsaw file or click it and press the laod button.

Second way - Note that this method gliched the map out a little for me and my brother
1) Click solo game
2) Click quick battle
3) On the right side of the screen you'll see the battle customisation area. Under the Game Rules tab select scenario
4) Then in the scenario tab that'll pop up select the World War III- Siege of Warsaw map
5) CLick Start

I need help. I purchased the game, but cannot figure out how to get to the game to play it. Help?