Report placards go on every auditorium and every restroom — a men's and a women's to start, and any others you add — and on any other place set up with a code; each kind of place can ask its own list of issue types. Once switched on, film rating placards go on the screen doors and match a rating to the showing in that room, and one visit rating placard goes by the exit. The QR placards page prints one set at a time — Issue reporting, Sentiment, Seats — because a sheet of cards that all look alike is a sheet somebody mounts in the wrong place.
Every code is a random token rather than a screen number, so codes cannot be guessed. An admin can rotate any of them from under its card, and the old code stops working the moment the button is pressed.