I played then demo when it was half finished too! I shouldn't have downloaded it at all.
In the first mission I have to go steal a jeep. Problem is, when it says I'm 0 meters away from the freaking jeep, i'm standing in the middle of a damn road with no vehicles in sight!
I kept getting shot by soviets I don't see. I'm trying. Each time I played the level, I kill another guy, but I either always missed one, or there were more than before.