Have you changed your diet or exercise patterns much as a result of the book and CD? I like listening to it to help me get to sleep, but I find it's most useful in making you happier about eating fresh fruit and veggies and exercising more. It really helps in making behavioral change easier, but if you don't make the changes I don't think it would achieve much for weight loss.
I lost a couple of kilos initially on the Gabriel Method but my weight has plateaued now. The difference between when I was losing weight and now really came down to diet and exercise.