Writing or importing XML DocBook documents in LyX needs the following installed:
the XML DocBook DTD 4.1.2,
the Norman Walsh DocBook XSL stylesheets,
an XSLT.
One of the problems encountered in using XML tools is the compliances between each other. According to some experiments, we can say that:
The DocBook XSL stylesheets version 1.29 don't work with XT.
To use XT, use the stylesheets version 1.34 or later.
To chunk with XT you need to use the xtchunk.xsl stylesheet instead of chunk.xsl
Until now the best translators seem to be:
xsltproc (Gnome libxml2/libxslt),
Xalan Java Version 2,
Saxon 6.2.2,
XT/XP.