I probably could not explain it correctly.
Part of the disc will be transferred to another disc.
Then all the additions I have made to the files (disc title, tag, artist, etc.) are not transferred to the files in their new location.
If you follow the directions, your edits, etc will follow the file during transfer. I would suggest reading the FAQ again.
There are a couple of important points. At no time can you let Roon see both files in the different storage locations, doing so, will have Roon tread the other files as new and thus will not move your library edits to the new location.
You need to disable all storage before doing the transfer, then move the files, add the new storage location, let roon see the new location and rescan. Then, after all the files have been removed from the original watched location, you can Enable the original storage location.
Remember, make a backup of the database before attempting. And feel free to ask more questions before you attempt it if you need to.