A BLANK plate just to fill empty space if needed, but clicking on the center will give you the option to place notes as well.

A GATE input turns the LED on the bottom ON or OFF depending on input. In a generative patch, the blank plate can used to separate blocks of oscillators etc that create a specific part of the patch. If that section gets a control gate, the BLANK plate can then receive a gate at the same time, and the LED can show that section is active.