I found a few instances where I made levels by copy and pasting screens then went back and edited the tiles making them walkable. When i played the game the edge of the screen would stop me from entering the next room when I clearly have everything set correctly. I tried to reset the room to start from scratch and the overworld view turned black and would only let me select from the memory bank 3. This forced me to abandon those screen sections all together. I had to just move the path the player takes and use the surrounding screens but the black screen areas are useless.