>This has plagued me for a while. Anything dockable, when moved, throws up this shadow, offset up and to the left, making it nearly impossible to properly align things. I'm also seeing it too some extent in the Database Designer, probably elsewhere also. I've already deleted foxuser.*, and tried many different display drivers. Anyone have an idea of a solution?

If this 'shadow' vanishes when you stop dragging, then it's probably the hint frame, i.e. the space your dragged window will occupy when it docks. It's supposed to help you decide - if you drop while a hint is active, your window assumes the position and size of the hint.

Of course, your hint frame looks rather different from mine, but I think that's just a different widget your flavor of windowses uses.