I uploaded a file to the ‘saved folder’. It seems that I can only link the file if its on the board.  Is there a way to link a file in the saved folder without putting to on the board? And if so, how?

More detail: Im using this board as a production/workflow.  So I would like to add proposals to each box. It would be a lot of proposals sitting on the board that I think are unnecessary if I can link to them in the saved folder.