Part of my process in making games, is making these quick drawings. I make these to get a sense of what i should add and what ideas are better left on the floor. 

for this drawing, I was trying to figure out how I might add a bit more colour to the visual identity of the game, without ruining the grey/black/blue feel of the game. that is why I added the orange door, to see how I might be able to get that to work within the world. 

There is still some work to be done in trying to make sure that these colours mesh completely and more yet, to get it into the game world, but this is a first step.