well. having read the prs+ supercedes this plugin, for Sony readers, I installed iprs+ to my sony 650.
but when prs+ chooses the current book cover for standby picture, it does not use the cover thumbnail that I see on main-ereader screen, and that I maintain in calibre; it seems instead to look in the .epub and use page 1 ( which may or may not be same as cover art- I often delete that one inside the book! so unless there's a way to tweak PRS+ behaviour, I'll stick with the plug-in + choosing covers manually.
I think I have to re-run epub to peub with metadata ticked to re-add cover art inside of book, and that re-adds the book summary from metatdata also, whether I want it to or not ?