My music files are stored on a NAS. I do not add any new music files to the NAS unless I have properly tagged them (I have my own tagging scheme so I will retag everything basically). So I tag just those new music files by loading in the folder that contains them and once tagged I will move them to the NAS and the main library in JRiver on my dedicated music computer will update itself.
The tagging process involves changing directory names, artist names, album names, the usual stuff, and I will use at various times the Artist, Album, Genre, etc. panes to do this. This is way easier to do when the library contains only those files.
I thought this was a fairly simple request but it appears from the posts here that there is opposition to this. Obviously JRiver was designed as a "Whole Library" program and it will not work well the way I use it. To be honest though, it would work just fine if that checkbox were reversed.
I will just continue on as before and hope that I uncheck that box every single time I clear the library.