Have you tried dragging while holding down the CONTROL key? As stated a couple of times in this thread.
That's not my problem, I'm not
trying to move or copy the file. It's very easy to
accidentally drag and drop a track from MusicBee to, say, the desktop (as I described in my original post.)
The purpose in being able to switch the copy and move functions for drag & drop is to avoid moving a file out of place in the file system without meaning to.
Actually, now that I think about it an option to simply lock or disallow drag & drop from MusicBee to outside the application would also accomplish this.