Hi there,
I got your demo file and thanx for that. Quite interesting.
Check this attached rough image.The green is the land (which is for both the top and bottom worlds). The character should able to walk on the green and when it falls down on the right edge, it will go to the bottom world where it flips and walks upside down there.To do this, is that the same procedure to follow. Because you have used a sprite which allows the character to go upside down when reach near.
How does this works (When a character falls down on the right side (Where the arrows goes), it should fall like it is falling inside the water. Goes bit down comes back up flipped.
Help and thanx