What other code? Edit - oh, now I see, in reply #10...
Your reasoning is flawed - it's like saying, "I fully understand a circle, and I fully understand a hexagon. I just don't understand why the hexagon won't fit in the circle"...
Also you made it difficult for anyone else to understand the program, since it has absolutely no comments or explanation as to how it works.
It's not possible to know which lines the "working" lines that you posted, are supposed to match in your sketch. So it is impossible to know the exact context in which they work. Really, this places too much burden on any people that want to help you troubleshoot this.
Also - your code is hard to read for other reasons, too. You never use standard indentation for your code blocks, which can be done automatically in the IDE using ctrl-T or finding auto-format in the pull down menus. Even before that, you should fix the higgledy piggeldy gratuitous use of blank lines and multiple brackets on a single line.
Why? Because it makes it easier to read, and thus easier to troubleshoot.
Please #include the huge array as a file like:
#include "hugeArray.h"
Format the remaining code so we can actually read it, add embedded comments to explain what it does, and post again in a new post. Don't repost the huge array, it's useless to us now that we have a general idea what it looks like.