I have a big with the cursor that is making the game near unplayable now. 

Each spot on the map is a square.  The spot should "highlight" a light gray to display it is the spot that the cursor is currently over. I am having a bug with the wrong spot being selected by the cursor. 

A square has four quadrants. With the diagonal view, they are top, bottom, right and left. It seems that when I zoom in and hover the cursor over the top quadrant the correct spot is being highlighted grey. When I hover over the right quadrant, then spot to the right is highlighted, bottom, the spot to the bottom, and left the spot to the left. 

This came out of nowhere. I have restarted, saved, loaded, etc. and it is still there. It is also highly unreliable and it makes it near impossible to select quadrant with the mouse without zooming in all the way.