Hi Omegador, I have exactly the same problem, but I don´t quite understand what you did to solve it. Could you explain it please? When you say "When I restore the default location of the Downloads folder" which one are you refering to? since D is now turned into Downloads. I´m also very afraid to delete D.
Umm, I forgot what I did now that you mention in, but what you MUST try to do is unlink the downloads folder as one of the responders indicated, and then just dragging the folder to the D drive once you're done.
Play around with it, and don't worry about messing it up. It worked out for me in the end.