How are you still taking actions normally, if you are reduced to taking only a move or a standard action? Being slowed obviously is not normal.
Additionally a Free Action is not a Move or a Free Action. By telling us that under the effect of the Slow spell the target is only allowed to take one of these two kinds of actions, it means that he is not allowed to take any other kind of action. To still allow Free Actions and other types of actions the rules would have to say something like: "A slowed creature replaces the Move and Standard action it gets each round with a single Move or Standard Action."
I fixed that for you. A Full round would take from just before the charger's turn in one round one till just before the charger's turn in the next round.