> Yes, you do have to re-index your files if you change the path.
No you don't.. not if you use ThumbsPlus to move the folders into the new parent folder.
If you do it from outside ThumbsPlus, then it has no way of knowing what happened. Your thumbnails will be orphaned since no matching images can be found for them anymore. If you let ThumbsPlus do the moving, it can simply update the location for each thumbnailed image as it moves it.