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I tried to respond by email, but all attempts bounced.

The condition of the Ctrl key BEFORE you press the mouse button makes no
difference whatsoever.  You have to be holding the Ctrl key when you
RELEASE the mouse button if you want to force a copy operation.

Here's a simple experiment.  Select a file and begin to drag it (no Ctrl
key).  Notice that the file's icon disappears from the listing window.  Now
watch what happens to that icon as you press and release the Ctrl key
(keeping the mouse button pressed all the while).  In addition, the icon
that you are dragging will show a "+" while you are holding the Ctrl key,
indicating that the file is being copied rather than moved.
