Sorry, but it doesn't. Every synonym I can think of, of nothingness based on the idea of "increment" doesn't make a word/phrase in the box. I'm trying, but it's just not making sense to me. It's just a shame if there's no answer key since it cuts me off from the rest of the demo so soon.
I agree the second puzzle jumped up too quickly in difficulty, but it's not too hard on it's own. Once you see all the numbers inside the train cars, all the information you need to get the combination is on the tablet.