Current questions and answers regarding the map editor.

Hello! Please help, people (and other races)! I have a terribly silly situation. I decided to create a map for a friend as a birthday present, and I messed up with the dungeon. I can't give it relief or anything else. I can't even change the dungeon. And not because it's dark; I found the light switch. Please help a newbie "dig a hole" through it. I would be grateful if you could help me with other questions; I'll write to you in a private message.