Derp
sorry for the late reply. Nothing is really buggy. It is just that trees and buildings of same size should appear smaller when put into the background. But this is not the case in tw editor. Everything put into background via parallax looks like the same size in standard zoom. Meaning the real size of the object grew in size. You can see in the example map the houses in background are bigger when zooming out, when they should be smaller. But if it is intended that way it's not buggy. I don't know the use of it being that way. Maybe it helped convert the old maps to function properly with the new zoom feature? Idk
ah maybe the issue is just that parallax zoom is only rendered in-game and not in the editor? there is currently no way of scaling tilemaps in the background on default zoom