6) you are missing KS+, there are new grey platforms in this room. Dunno how you was able to make chicken hunt challenge ?
I just didn't see them because they blend with the background. I also didn't see them in my editor, because level format isn't set to KS+ (and I happened to have KS Ex set of objects chosen). To set format, set Format=4, rename Info.png into Info+.png and add Info.png with text that would inform how to install KS+ if the level is selected in another version.