Current questions and answers regarding the map editor.

Yesterday, I performed a similar operation on a randomly generated map in the Dungeon – the result was the same! I removed a section of wall between areas; by the way, why can't all walls be selected and deleted? The surface of the area under the removed wall is exactly the same as the adjacent area – it’s level, without obstacles, and with the same pattern – but it’s still impassable for the hero.
I would greatly appreciate more detailed information about this passability check and what “BLOCKED” means.
Thank you very much for your help!