The correct link is
https://www.mobileread.com/forums/sh...d.php?t=119175
In short, you can't change the structure of a Calibre library. And Calibre always creates copies of your files for its libraries, there's no way around it.
As to moving the library, just copy over the whole library folder in one piece. Then point Calibre to the new location (Library -> Switch/create library -> Use the previously existing library at the new location)