Grouping Question

Hello everyone,

  Let say I have an XML file that looks like this

<root>
  <L1>Data</L1>
  <L1>Data</L1>
  <L1>Data</L1>
  <L1>Data</L1>
  <L1>Data</L1>
  <L1>Data</L1>
  <L1>Data</L1>
  <L1>Data</L1>
</root>

  What I want to do is split this into multiple files each time a new L1 is
found. The following code is what I use. (The code for this is more or less
generic except for the XPATH).

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="2.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="utf-8" indent="yes"/>
    <xsl:template match="/">
        <xsl:for-each select="root/L1">
         <xsl:result-document
href="C:\\out\\{format-number(position(),'000000000')}.xml">
          <reportrun>
          <batch>
              <xsl:apply-templates select="."/>
          </batch>
          </reportrun>
         </xsl:result-document>
        </xsl:for-each>
    </xsl:template>
  <xsl:template match="@*|node()">
    <xsl:copy>
      <xsl:apply-templates select="@*|node()"/>
    </xsl:copy>
  </xsl:template>
</xsl:stylesheet>

  This works A1, just the way I want it to. Now what I would like to do is add
an option that would allow the user to do the same split but they could choose
how many "L1" would go into the output file. For example, right now the above
case creates 8 files, one per L1. I would like to output 4 files that would
each contain 2 L1 nodes.

  I tried something like this

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="2.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="utf-8" indent="yes"/>
    <xsl:template match="/">
        <xsl:for-each-group select="root/L1" group-by="L1[position() mod 5 =
0]">
         <xsl:result-document
href="C:\\out\\{format-number(position(),'000000000')}.xml">
          <reportrun>
          <batch>
              <xsl:apply-templates select="."/>
          </batch>
          </reportrun>
         </xsl:result-document>
        </xsl:for-each-group>
    </xsl:template>
  <xsl:template match="@*|node()">
    <xsl:copy>
      <xsl:apply-templates select="@*|node()"/>
    </xsl:copy>
  </xsl:template>
</xsl:stylesheet>

  Which did not work. Any insights as to what I would have to change to get
this going would be appreciated.

Thank you in advance.