Q: Is the passage to the spiritual worlds done during sleep and dreaming?
A: The wisdom of Kabbalah deals with the study of the laws of the universe, the structure of the soul and the management of the worlds. Your questions about dreams relate to the physical animate state of man. There is no connection between dreams and spiritual forces. Dreams indicate what happens in the body, not what happens with the soul.
Therefore, in order to attain spiritual elevation and attainment of the spiritual world, there is no point in analyzing dreams and there is no significance to the way you sleep. Our sleep is merely a physiological phenomenon, as in all animals.