For me , starting with 40 days beginner program was not the best idea, I'm still a beginner. I would suggest to start with Hell's Army Satanist training program of 6 months. The program is divided into 6 months and deals with everything from the very basic, so that will help to build a strong foundation.
The 40 days program directly tells to do certain stuff like visualize, or sense the energy or direct the vibration and gives idea about how it might feel. So a newcomer, who has no perfect idea about visualization or energy sensation, might struggle or try too hard, which can result in fake sensation of energy created from subconscious. Also, I used to struggle with visualization, but it is getting better everyday. The problem was underdeveloped third eye. The 40 day program tells you to start Chakra Spinning even before meditation to open third eye. Due to my problem, I was getting frustrated, I asked on the forum what might be the cause, and when I found out, I started doing the meditations and it's getting better Day by day.
But 6 months training program deals with the problems a beginner might suffer, from the very beginning. At first you practice visualization using various techniques and so on.
P.S. I believe one should do practice based on his /her necessities.