OK, the new (?) demo with OPSM2 seems to be different to the one that came with ZOE.
There is no very hard mode, and you can play more after Olga is dead. BUT - where is the USP hand gun??? It is NOT in the locker, and I can only seem to get it once I kill Olga, but is it hiding somewhere? I am sick of the dart thingo, and I want blood, so where is the USP in the new demo? There is still ammo for it, I just cant find the damn gun!