This doesn't happen all the time, but sometimes after returning from one of the desktop pages, a fence will be a few pixels narrower making the icons appear in a different layout. After slightly re-adjusting the width the icons return to their correct position. It may even be the gutter between fences that widens slightly on one side that causes the issue - not sure.
I'm using dual monitors (one is a different resolution than the other) if that has anything to do with it.
Also, it would be great if you would specify the grab-width for dragging the screen to a new page. It's a bit narrow at the moment.
