In fact, the character blocks himself when he wants to take stairs (located in the foreground, therefore the main area is in the background, which also has a depth effect that goes up on screen (so if I use a single way system, my character shrinks on stairs when logically it shouldn't).
This blockage is probably cause the action area I've created front of the stairs is only made to either enter or exit the stairs, but apparently not both at the same time.
Moreover the method I set up is quite unstable since when I tell with the default cursor to go beyond the area (located in another action area) ... the character doesn't seem to recognize it ...
I'd like to apply a condition to the action areas so as to set up a "toggle" but it seems impossible.