PzC looks like a good choice for a CM campaign with it covering all of the CM WWII theatres. PzC also looks like the most straight forward method I've come across and least burdensome in terms of admin. But is that just wishful thinking on my part?
Just to check on the turn steps, did you play the turn actions out in this order:
1. Player 1 takes turn, moving units and carrying out any 'non-assault' actions on the PzC campaign map.
2. Player 1 plots 'assault' actions, but does not press the 'resolve assault' button. Instead he ends his turn and sends PzC turn file to player 2.
3. Player 2 watches replay of player 1's turn.
4. Assault battles played out on CM and casualties are incorporated in PzC OOB using PzC editor.
5. Player 2 carries out turn in the same manner as above (although must withdraw any units defeated in the CM assault).