Icons No Longer Move Into Or Out of Fences

I have been using Stardock Fences for several years now with no problems.

Starting about 2 weeks ago, I am no longer able to move icons into or out of any of the fences I had set up (although I still can delete icons from any location.)

When I try to move an icon from the desktop into any fence, while I can still drag the icon to any location, when I release it the following happens:

1. Two adjacent icons in one fence move out of that fence and then disappear (It's always the same two icons in the same fence, regardless of which fence I am trying to move the desktop icon into.);

2. The icon that I was moving then goes back to its prior location on the desktop: and

3. The  2 icons that had disappeared move back into the same positions in the fence where they had moved from.

(There was also a third icon in another fence that moved as well, but that one moved so that it covered another icon with a similar name in that same fence.  It then moved back to its original position as the desktop icon was returning to its original position.  All of that occurred at the same time that the disappearing icons moved and then returned to their positions.  I deleted this third moving icon, but that did not correct the situation.) 

Any suggestion on how to correct this problem?