I have not played much, ok once, with CD but the current version CD (the fourth) aka CD:Test of Battle is a winner in my mind. So much I bought a copy. It is not simple but is is a much more streamlined version compared to the rest, and has more uncertainty (fog of war cards - sort of random events), which is only a good thing for ww2 battles.
The other versions are ok too, but TOB in my mind has hit a CD sweet spot.