Questions & Answers about Nicht jedes Wandbild in der Stadt ist legal.
Why use nicht jedes instead of negating with kein?
Kein means "no" or "not a single one." If you said Kein Wandbild ist legal, it would mean that strictly zero murals are legal. To say "not every mural" (implying some are legal and some are not), you simply place nicht before the determiner jedes.
How can I relate this to the lesson's formal structure die Erlaubnis haben, zu...?
The adjective legal implies having permission (similar to the modal verb dürfen). While this specific sentence uses an adjective, you could express the same legal concept using the lesson's target structure by rephrasing it slightly, for example: Man hat nicht für jedes Wandbild die Erlaubnis, es zu malen. (One does not have the permission to paint every mural).
Doesn't the verb have to be in the second position? Why are there so many words before ist?
The verb ist actually is in the second position! The entire phrase Nicht jedes Wandbild in der Stadt acts as one single, large subject block occupying position 1. The prepositional phrase in der Stadt is simply an attribute describing the noun Wandbild.
Why does jeder end in -es here?