AFT won't move large files all at once. Trying to move the Music file won't work. I found I had to move groups of folders. Commander One will move the Music folder, but not while in freebie mode, apparently. No idea re Windows, if drag and drop that might be easiest. As to disappearing files off the SPK, if you are inadvertently deleting them by accidentally using the trashcan, they just poof away. I've never had files just disappear on their own. If tagging is off, or they aren't placed correctly in root, they can be hard or impossible to find without going to Folder view.