Testing the default 50x50mile center box with 4cirrostratus.
I gave it .75min time to live, I'm not sure if the 50x50 block generates, then moves for .75 as a block or, it keeps generating inside of the 50x50 pushing it at 70mph for .75min.
Produces a very nice cloud system inside of the 50x50, I was able to fly very near and no FPS drop. Inside it can drop very low and bounce up and down depending on how close to the outer edge of the puff ball I am. Two of the screen shots show rendering issues looking at a diagonal down the length of a wide cloud formation.
When you say overlapping is that one 50x50 higher than another slightly past the lower one's boarder running over it or, two 50x50 next to each other even if they do not touch?