According to the cruise agent when I booked my cruise, there will be no charge for the zip or Aqua theater shows. As with ice skating on previous cruises, there is no charge.
There are usually large production shows, no charge, 3 nights, but there is also comedy, maybe a magician etc. to fill up the other nights. At 2 shows a night, that 2500 guests that can be accomodated.
Since I don't have kids I'm not sure about that one but have never heard of a charge.
I am going on the Inaugrial curise 12/05 and will let you know more afterwards.