You could insert some "@confirm" statements into all the drag and drop events to be found here:
Settings -> Filetypes -> All Files and Folders -> Events (Tab)
Another possibility is to restrict yourself from moving (which is a copy and delete) files and folders by applying reduced access permissions to these.
I use these: Lock On/Off (protect items from deletion) They require a NTFS filesystem I guess. But whatever filesystem your NAS uses, it should have some way to allow only a subset of file operations on specific directories for specific users. I do not own a NAS, my drives are attached to a regular PC that is running constantly, so don't mind if I talk BS. o)
The key is to not access sensitive areas as "root" or "superadmin" or whatever master account in question.