If one side of the ground has a black line, like a border, the rest of the sides should. Some tilesets don't have 1-tile wide squares, so you'll have to work around that. You could have, however, used default tileset 148, 149, 175, or any other tileset with outlines, set the ground as layer 2 and set the border around it as layer 3.
Also, after you get the ghost eye and you go to the area to the left of the umbrella, there's dripping ghosts on top of a row of ghost blocks. (Wow, 3 ghosts in one sentence. lol) It's possible to jump into those blocks from the left side, ending up in a wallswim. If you don't know what a wallswim is, go to the level editor and put Juni into a third layer object when testing the level.
