Current questions and answers regarding the map editor.

Hello, kind people, please help me figure this out, I have a problem and I can't understand it! I created a map using a generator, and then opened it in the editor to make some adjustments. The map was created from several isolated areas connected by teleporters. But the computer lags terribly on these teleporters, even at the highest settings. So, I decided to connect these areas of the map directly. To do this, I deleted trees and other objects in the editor, creating a direct path between the areas. But when I entered the game, I found that I couldn't pass through these areas; the hero's movement cursor in these areas turns into a red crossed-out circle! The surface is clear, there are no obstacles, but the hero cannot pass through this area - it's inaccessible! And even if there is a building on such an area, it is also inaccessible! Please tell me what the problem is! And how can I overcome it?