[kiwidude]

What are you actually trying to achieve? Do you have books on shelves in Goodreads already that you are populated a genre column in Calibre for, or are you trying to put books on Goodreads shelves based on their tags?

Looking at your mappings, you have multiple Calibre tags per genre. I wonder if you are making the mistake that someone else made recently on this thread of trying to use uploading to Goodreads as a way of "cleaning" their tags. You cannot do this. The way you have setup your mappings for a "short-stories" shelf to have tags of "Short Stories,short story". What this means if you were to download shelves as tags that a book on the "short-stories" shelf will get both tags applied to it in Calibre. The same works in reverse - this mapping is telling the plugin that a book must have both those tags on it for it to be uploaded onto the short-stories shelf.

Now in terms of your "mappable items" exactly what screen/field are you talking about? The edit shelf/tag mappings screen will let you create one set of mappings per goodreads shelf. If you have added a shelf using the goodreads website, click the refresh button to make sure it appears in the configuration dialog, click edit shelf/tag mappings, and then click the green + icon to add any shelves that exist on your account that are not currently listed in the mapping screen.