.@manton @pratik your custom theme is your custom theme. It exists entirely separately from the plugin. The way that Hugo merges directories means that my plugin can look for a particular data file that exists entirely outside of the plugin. This is why I use a different path (dash-cased) to avoid collisions.

I take the data file templates / default parameter value files held by the plugin … copy/paste into a single file … add adjust for file level (add [Config], [Style], and convert to [Bookshelves.Registered]) … and then save that in my single custom them (Moondeer).

You can see all my plugin configurations living in my custom theme:

Y'all are making it more complicated than it actually is.