yWriter5, for Windows PCs:
Recommended instead for Mac OS/X users:
Create Ebooks using yWriter and Calibre
A how-to guide based on my own experience
See Guido Henkel's useful articles on html ebook formatting
So, yWriter 18.104.22.168 introduces a new 'Export to Ebook' feature. This routine will export your novel to an html file which is optimised for conversion using Calibre. The resulting ebook should be formatted correctly without any nasty surprises.
But what if your novel is currently sitting in a Word doc, or an Openoffice file? Easy! Save it as RTF (all word processors support this option), then import it to yWriter using Import a work in progress. Once it's sitting in yWriter, export to ebook and convert the resulting html file using Calibre.
To summarise, you can create ebooks like this:
yWriter5 > Calibre > Ebook Reader
Or like this:
Word/OpenOffice > yWriter5 > Calibre > Ebook Reader