This is what I want:
But when I replace the path back between the walls, I get this:
I placed the fading brushes like this:
When I place them more inside, it doesn’t fade at all.
When i place them more outside, it has the same effect.
In both of the first screenshots, the fading brushed have the same position.
Now, how can I make the path between the walls blend like in the first picture?

