The blank area under "READ THIS ON" usually means it's a PDF which AFAIK can only be downloaded from the library on the website and not into Kobo apps or AFAIK onto Kobo devices directly. Need Adobe Digital Editions to download and of course a working server on their end.
IIRC someone else (crich?) recently posted that they had bought a PDF book from Kobo and couldn't get it to download. Kobo ended up claiming the book wouldn't download due to formatting problems and issued him a credit.
EDIT: Here's the thread I was thinking of...
https://www.mobileread.com/forums/sho...d.php?t=244330