Added 8 minutes later
By the way, after completing the walkthrough, I read the novel by Polish writer Janusz Zajdel, after which the map is named (in the Russian translation, "The Limit"). It's a mediocre dystopia, but not without some interesting moments. The action takes place in a fictional city, where society is divided into seven social classes, numbered from zero to six, and distributed according to the intelligence quotient of the citizens. "Zeros" are considered the elite and the dominant class. The class determines what position a resident can hold and, accordingly, what work they can perform. Class status is determined by passing a special test. I think that Sprocket's idea as the map's author was that his map is this test for "zero" status.