Customizable Display Puzzle

This is a puzzle that isn't for you to solve, but rather for map makers to include in their maps. It's a 4x3 grid of squares that, when the solver puts in the right squares, a reward is given, whether it be an item or progress - the choice is up to the map maker.

There's also an area where the map maker can go and set the right combo, meaning that whatever they put in is what must be sent into the other end to get the reward - no more, no less, only the exact right code that was set by the map maker.