Thanks for the feedback!
I attempted to make the colors match the stations themselves, but I like the idea of coloring the corridors to match the station/threat as well :) I was planning to throw in an arrow signaling which station was ready, but that would have crowded the UI a bit too much.
I chose ZXCV specifically because they aren't movement keys and it made the player really think about which key to press since most people don't use those keys often enough to have them bound to muscle memory ;)