The Curves Smart program is really great. I just worked the machines for the alotted 30-seconds on and off for the first two weeks of the program. The get used to each machine, learn the proper form and concentrate on using the specific muscle groups.
The next step was Curves Smart. Each machine is calibrated to you. It learns your range of motion. You can then see if you are working the right muscle group. It also shows you if you are working to hard or not hard enough. Maybe you need to push harder or pull more or even extend your leg or arm on a specific machine. I found it hard the first time you go through the workout ONLY because you are learning something new while exercising. The second time was soooo much better. I REALLY like this aspect of this workout regime. It gives you so much feedback. That really helps you understand what you are doing. And in some cases not doing.
I got a 97% on the first workout...which you are striving for 100. The second was 100%. That told me that I'm pushing all the limits but not too much. It makes you feel really good to see the results from the machine on a computer screen. You feel more connected to the workout.