I grasp that, I was trying to move parts over across the ground. So I would pick them up and set them onto the ground and they would explode or fall through the world. Not a problem with this mod, it looks to be a problem with KIS that can happen. "Known issues - Small parts dropped can go throught the ground or explode. I recommend to avoid dropping them on the ground directly, and instead drop them on another part (container for exemple)" from KIS page