I assumed that the /epub directory is still supported (although the ruby script might not work).
If it is the case that /epub/docbook.xsl is no longer supported, then there would probably be a need to have a epub2 backward compatibility option for the epub3/ stylesheet.
The Smashword error messages indicate that they are unable to read epub2 features:
********************from smashwords
We have run EPUBcheck on your file, and unfortunately, it has not passed validation. The errors found were:
Smashwords is quickly becoming a major distributor of ebooks -- although they've been using an older verison of epubcheck. They accept only epub files which can pass the older test.
Robert,
If I remember correctly there is an epub directory in
the stylesheet distribution that creates epub2. It is unsupported as
Keith is no longer maintaining it. It may still be a good starting
point.
Carlos
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Robert Nagle
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