Add one or more parameterGroup configuration elements to your custom .xxe file:

<parameterGroup name="Name of the parameter group">
  <parameter name="Name of parameter #1">Value or parameter #1</parameter>
  <parameter name="Name of parameter #2">Value or parameter #2</parameter>
  <parameter name="Name of parameter #3">Value or parameter #3</parameter>
</parameterGroup>

Which parameters to specify is found by reading the documentation of the XSLT style sheets. For example, the reference manual of the DocBook XSLT style sheets is: DocBook XSL Stylesheet Documentation.

Example: Use UTF-8 encoding when convert DocBook documents to multi-page HTML:

<parameterGroup name="docb.toHTML.transformParameters">
  <parameter name="chunker.output.encoding">UTF-8</parameter>
  <parameter name="saxon.character.representation">native;decimal</parameter>
</parameterGroup>

Example: When converting DocBook 5.0 document to RTF, WordprocessingML, OpenDocument, OOXML or to PDF, PostScript, style variablelist like XXE does it on screen. That is, do not put the term and its definition side by side.

<parameterGroup name="db5.toRTF.transformParameters">
  <parameter name="variablelist.as.blocks">1</parameter>
</parameterGroup>

<parameterGroup name="db5.toPS.transformParameters">
  <parameter name="variablelist.as.blocks">1</parameter>
</parameterGroup>