v8.1.18
Well that’s interesting…
I initially copied 6 components (A2 and A3), pasted, and then I held down alt+right arrow keys to move it across. Instead of moving as one, they move as individual components and obviously some miss some of the key events and slip behind the others…
are you in percent mode?
Nope fixed 
That happens to me as well, very annoying. Only seems to happen when using keys, dragging via mouse seems to work fine.
I have observed the same thing, and that moving slowly, i.e. tapping the arrow key only about once a second, greatly reduces the occurrence of objects that “drift” during the move. Dragging via mouse is fine for getting a group of objects in the general area I need them in, but the fine adjustments using the arrow keys are oftentimes needed.
I would like to see a way to effectively create groups of objects to make the moves via arrow keys without putting everything I need to move in a container.