Dynamic Campaign Generator (DCG) is a mod for the game "Men of War" and some of its successors that randomly generates skirmish missions and lets you keep your surviving forces from one battle to another. Some people find this mod tricky to install the first time - please read the readme.txt carefully and ask for help (if you need it) on our forums here on this site, or at the game developer's site.
DCG v4.0
The English tanks always stood out to me with how they look. I learned recently that many were designed with trench warfare of the previous war in mind so maybe that explains it.