With the game paused, when you clone a section and place it, then clone another section and place that, the first cloned area you placed becomes the second cloned selection. It's hard to explain so I've included a video. 
Steps:
To reproduce this bug do the following:
Pause the game.
Clone anything you want.
Paste what you cloned.
Clone something different.
Paste what you cloned.
Unpause game and watch your builders mess up.
