Yes, that's exactly, what I also try to do.
But on my Aura HD, there is no option for a rating, when choosing the details screen of a book from the library.
Please see attached foto.
In my opinion, the rating option should appear at the position marked with a red frame, shouldn't it?
What I did until now:
- I uploaded all my ebooks via Calibre software (epub)
- I did a factory reset of my Aura HD
- Reinstalled the Aura HD by syncing firmware via Kobo account (v3.18)
- reinstalled again all the above books
There is still no rating
(On my other device, a Kobo Glo, I have installed the same books, also using Calibre. The Glo runs firmware version 3.8.0 and the rating just works fine.)