I think there is a situation that MWiF will get wrong: Moving through a port containing a non-cooperating unit. This should be legal, because stacking is only enforced at the end of step, but MWiF won't let you move onto a non-cooperating unit.
For example, a Dutch cruiser stacked with a CW INF division wants move through Alexandria, dropping off the division and winding up at sea. Unfortunately, there is an Egyptian TERR in Alexandria. I believe the move is legal, but MWiF will not let you do it, although I haven't checked.
Before I spend any time checking that MWiF does not let you do this, I want to be sure that it's legal, first. So, is this legal?
I thought I knew how to play this game....