#1 is ledges; #2 is passability.
#1: I've tried putting my ledges on every layer imagineable, but for some reason, when you're walking on the ground or behind a tree, you can walk on top of a ledge that you shouldn't be able to. When walking on top of the ledge itself, trees marked 4-5* will actually appear on top of the character, as seen here (the ledge is on the 3rd layer; the tree is on the 2nd layer):

Tree *:

Ledge passability:

I'm also able to walk from the first layer on to 2-3rd layer items, as seen here (1st layer grass -> 3rd layer ledge):

#2: For some reason, a 2nd-layer mushroom, normally that cannot be walked on (it's marked with an "x"), can be walked on when behind a 3rd-layer tree, as seen here:

But it's obviously unpassable, by my settings' standard:

Can someone help me figure out what's wrong? I can't release like this :s