Jerry,
Thanks for the extremely quick response. Unfortunately, your suggested solution doesn't seem to help, at least not for me. However, while trying out your suggested solution, I believe that I came across (or stumbled upon) a workaround.
In particular, the issue only seems to arise if a Medved application window is selected/highlighted when I switch virtual desktops. It appears that the Medved application windows remain in whichever virtual desktop they were last selected. So a simple workaround is simply to select, i.e, click, on something other than a Medved window before switching virtual desktops
Finally, I should note that I'm using Parallels in its "Coherence" mode. In this mode, Parallels hides the Windows background and makes each open Windows application behave like a Mac application, thereby allowing the user to move the (Windows) application windows to different virtual desktops and physical displays.
Thanks again for your help.
mdr