I have now installed fbreader 0.9.2 version with the extensions file
https://www.mobileread.com/forums/sho...=pb360&page=10
from Schnitzelbrain. Everything works fine and I can now see all images. It seems that the native version is a problem. I can also see the toc. If you use sigil for conversion to epub I think you'll find it very satisfactory.
Basically from and file e.g. html screen read to openoffice word and do any adjustments. Then save as openoffice html. Then into sigil and do toc and section breaks. You can use the first page as a cover or do a separate image for cover. Sigil allows you to fine tune much more than calibre.
For pdf you need to ajust end-of-line hard breaks first.