Can't move/drag the pop-up windows (inventory, etc.)

So, ever since I began playing two months ago I haven't been able to drag/move all the pop-up tabs (the inventory, equipment, skills, ability, meso drop windows...) more than 1-2 pixels at a time. And they have limits as to where they can go. Some can't go left, others can't go down, etc. Any ideas as to what might be the cause?

 

I just tried two other mouses and my touch-pad. Still won't work.

 

It doesn't seem like it either. It works fine everywhere but in Legends for some reason.

 

Issue resolved. Seems like a flipped button (left/right) setting was the issue. But still, shouldn't cause trouble in the game, should it?