Originally Posted by Toxaris
And don't forget, an ePUB is not the same as HTML. There are differences in rendering, so a web-renderer will display something different compared to a dedicated ePUB-renderer.
That's somethiing really immortant and it had escaped me. Re the file I initially mentioned, I don't really need to have it as EPUB: I also made a PDF when I made the initial HTML version (both from an ODT file, if I remember rightly), and the PDF reads well in the android e-book reader. I only made the ePUB to try SIGIL, and only put it online because I was puzzled by its not working and wanted to ask here. All your replies have been most useful, and I'll bear them in mind next time I really need to make an ePUB file.
Thank you all