I live in the southern hemisphere. Should I apply the bagua in a different way with North on top?
No. South in Bagua is always at the top. Feng shui deals with magnetic field. Magnetic South Pole is on the top of our planet, in other words – not far from the Earth’s North Pole. North magnetic pole is near the Earth’s South Pole. Magnetism radiates from the North magnetic pole which is near the geographical South Pole. Radiation is the characteristic of the Fire element. So the 9 Fire in the Lo Shu square is on the top. Such characteristics as fire, hot, summer etc. referring to the south in Bagua are used as associations. In the same way water, winter and cold are used for north in the Bagua.