Hey @Darrell_Herrmann – @support just brought this to me and we took a look. This is a bug 
The issue here is that Peggy Lee only exists in your library as a composer – she composed two songs that are performed in your library, but she actually has zero performances of her own in your library.
So, in your library she is a composer, and it makes sense that Roon is presenting her to you as a composer. The bug is that you should also have a tab giving you access to all of her work as a performer from outside your library, as shown in @Martin_Webster’s screenshot above.
We are able to reproduce this issue, and we’ll get it fixed (although it’s a little late for the fix to be included in our next release).
For now, you can work around this issue by adding a single Peggy Lee performance to your library – you should be able to search for her albums, or navigate to one of her albums from the composer page (by clicking on the cover). Once you click “Add To Library” I suspect everything should be working as expected, but let us know if that’s not the case.
Thanks for letting us know about this and sorry for the trouble here!