No, not exactly.

If you don't like a move, or you can't do a move, or you can't get a move...ditch it and a replace it with a move that you love and that fills the gap appropriately. 

Keep in mind however, that this applies only to moves that are mutable. In other words, you would take leave out a move like the Earth Shower, or the Closing Mudra and replace it with something else. These are foundation aspects that will not change significantly. But let's say you really don't like the second move in Cardio B. Great, we love it when you customize. So, find another move that fits in that spot well and do the switch. Keep your transitions in mind and notice how it effects the rest of the routine energetically. It should still make sense. Have fun and be creative. We want you to love all the moves you teach, and nail them!