The are many calculations and theories within various family systems, both open and secret.
"Which Feng Shui system is correct or best?" is right up there with "Which Kungfu is best?" Each has it's strengths, and unfortunately, like some martial arts instructors, you'll find some Feng Shui teachers putting down "other" system.
You find a system and teacher that has results and resonates with you, then work with that system to gain a deep understanding of it, and then explore other systems.
Chances are, you have a 1973 birth date and the "Wood Element" Marie has listed in your Personal Energy Number Chart, represents your "Fortune Element," which is based on a different calculation than your "Year Element," which some online tools will show you, and different than the "Metal Element" that is connected to the number "6," that you'll see on the chart on P.13, as well as listed on other Feng Shui internet Tools.
At a personal level, Marie finds that working with your fortune element makes a bigger impact than working with one's year element. When you are activating general space feng shui in the Level One course, then you will be activating the different sectors of your home with that direction's number, element, shape, material, colors, and symbols as found on P.13.
Much Love, Shawn