Changing metadata, including adding custom columns, does NOT change any in-library format files.
If you want to inject the current metadata into the in-library format files, you must use the Polish book or Embed Metadata tools, or the Modify optional plugin.
If you Save a Book to Disk or Send it to a Device, the format file(s) saved/sent will contain the current metadata, but the in-library copies won't change.
Can I suggest you a) familiarise yourself with the
User Manual, particularly the '
The main calibre user interface' and the '
Frequently Asked Questions' sections, and spend some time watching the
Video Tutorials. I normally loathe video tutorials, but the ones Kovid has made for calibre are excellent - watch a segment, then do it on a test library - repeat if necessary.
BR