Find qualified Teachers
Look at other books on sleep and dreaming from more authentic resources, (e.g. the Tibetans Tenzin Wangyal Rinpoche, who has a simpler, more direct, and valuable audio recording, and the text, The Tibetan Yogas of Dream and Sleep; and Chogyal Namkhai Norbu, and western mind specialists such as TH Ogden and JA Hobson). Do you want to be scared into listening to something, or find more reasonable sources to explore a worthy topic? Add to Tenzin Rinpoche's recorded teachings, the text Dzogchen (Heart Essence of the Great Perfection) text by His Holiness the Dalai Lama, and you will better learn and master.