[DNSB]

After looking at Karellen's epub, the issue appeared to be with the blockquotes around the Tengwar display of the one ring quote. If I removed the blockquote which is not really needed for a centred text, it worked. If I added the font-family declaration to a class used for the blockquote, it also worked. For kepub, you still need to use the publisher default font (or start playing with the patches).