All the bookshelves are showing You don't want to share your shelf
Well, at least I know it's not just me that's doing something wrong as that's what I found too, same with the wish lists.
You can still get to them through the member's profile page. Not a fix, but a temporary work around anyway.
I just sent in feedback about this!! :)
It must be fixed because I cn access them from the "bookshelf" button now.
Thank you for your patience