Not sure if OP is still in the discussion, but if you are looking for a WWI scenario, you might be interested in trying Darkest Hour. It was published by Paradox, is based on the HOI2 engine, and includes separate WWI and WWII scenarios. The game is still being updated and last I heard the devs were attempting to connect the WWI and WWII scenarios into a single grand campaign.
It is also quite inexpensive. You can check it out here:
http://www.gamersgate.com/DD-DHHOIG/darkest-hour-a-hearts-of-iron-game