Calibre EPUB throwing exception on Cybook Odyssey

Hello,

I have a Cybook Odyssey device, tweaked by a library here in brazil (mainly translations and settings to connect to their book repository) and branded as Saraiva Lev

I was trying to convert an html page from web,

https://engsoftmoderna.info/cap0.html

to an EPUB using calibre. I downloaded the whole pdf page (including images) to my computer and used calibre's "Convert books" feature, to make a conversion to epub.

The output epub file runs fine on my computer: the images are present and well positioned, text reflow, page breaks, etc. The problem starts when I try to open the epub file on my odyssey device. It tries for a while to render the file and crashes.

I checked for some other epub files I have, and they seem to have the same structure with html files.

Is there something I'm missing?