I've always had that in the layout editor as well.
Many times you can grab one of the boxes and drag it in circles around the screen and all the previews will snap into place. Then drop it, hit undo to put it back, and your good until next session.
different X/Y Parallax on layers will cause weird fisheye affects on layers sometimes too, that trick also fixes this.
However the trick doesn't always work.
Here's a Youtube Video: