Trying to fill an area with CC3's hex grid
So, I have a 1200x1200 background I want to use to build a stylised map on top of. That's great only when I create a 1200x1200 map in CC3, the hex grid only covers 9/10ths of it and leaves a bit at the top uncovered and a massive chunk off the side completely blank. For the life of me I can't figure out how to get it to line up properly and fill the entire area.
This would be fine if I could reverse engineer the exact area for the hex grid and then resize the map to it, but I can't even figure that out!
Help? Please? Take pity on me and my inability to comprehend the iniquities of CAD, and the tyranny of evil programs, and we shall strike down upon them with great vengeance and furious anger, those who attempt to poison and destroy my projects!