This fairly simple xslt gives errors in XQilla-2.3.2.
=== simple.xml ===
<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:xslo="urn:dummy" exclude-result-prefixes="xslo" version="2.0">
<xsl:output indent="yes" method="xml"/>
<xsl:namespace-alias result-prefix="xsl" stylesheet-prefix="xslo"/>
<xsl:template match="/">
<xsl:message select=""'A new XSLT'""/>
<xslo:stylesheet version="2.0"/>
</xsl:template>
</xsl:stylesheet>
=========
$ xqilla -s simple.xsl -i simple.xsl
simple.xsl:4:70: error: Unrecognized XSLT element {http://www.w3.org/1999/XSL/Transform}namespace-alias [err:XPST0003]
<xsl:namespace-alias result-prefix="xsl" stylesheet-prefix="xslo"/>
simple.xsl:6:53: error: Unrecognized XSLT element {http://www.w3.org/1999/XSL/Transform}message [err:XPST0003]
<xsl:message select=""'A new XSLT'""/>
http://xqilla.sourceforge.net/XSLT2 aknowledges that these are missing. For common use, especially xsl:message is important.
simple.xsl