Rand...it's best to start with the Puzzles and mix in some Complexors as you go. I did it last year with my 4/5 combo and we sailed through it. They were really doing a great job with it. This game breaks down the simple skills and gives them tons of practice on small sub-skills that make up writing. If you think about it, the greatest golfer that lived doesn't go out there and play 18-36 holes of golf each day. No, he goes to the driving range and hits 150 shots with his 7-iron, and then 150 more shots with his driver and so on. He is fine tuning the small parts of his game so that he can play the big game better.
Kids need tons of reps on the little skills in writing. Puzzle one makes them take a group of items and break it into parts...first two parts, then three and then four. The pacing is really up to you, but the key is tons of practice. Don't start writing until about puzzle 5 I believe. That sounds weird I know, but they get so many more reps in orally this way, and then their writing becomes better faster.
Look into doing this with our new Oral Writing and the two will take off together!
Power to the Teacher!