Hello Flourgrader!
A disadvantage of having several libraries with a radio list copied in all your libraries, is that any change in the radio list must be reflected in all its copies.
Without knowing why you have divided up your collection into different libraries,
I can also suggest another method: managing ONE library for your whole music collection + radio list,
but using the 'Filter' feature.
Filters allow you to see only a subset of your collection in the 'Music' tab, which leaves the radio list untouched and assures you that it's always present.
Thus, as for the radios: one list to rule them all.
And as for your song collection, you can achieve the same result (browsing only a subset of your tracks),
but with even more flexibility: you can adapt your filters without needing to go back to the drawing board for your folder structure, for instance.
Filters are easy to define:
* Right click on the 'Music' tab header
* Menu Filter -> Manage filters
* Enter the filter names and their matching rules (button '...')
Once filters have been defined, you can apply one (or reset filtering) the same way:
* Right click on the 'Music' tab header
* Menu Filter
* Select the desired filter (or 'No filter')