Stop Office for Mac from loading with earlier documents on top of the one I opened?
Quitting the app with Option + Command + Q will ensure all windows are closed, and on the next open, only the intended file will open.
Go over to ~/Library/Saved Application State/ and change the permissions of your intended folder (com.microsoft.Word.savedState) to read-only.


These are essentially hacks - both tested on OS X 10.10.3 (Yosemite) and works.