Merge 2 XML files with identical siblings using XSLT

In continuation of question "XSLT to Merge 2 XML Files" XSLT to Merge 2 XML Files

I have following doubts: 1) How to handle cases where nodes having same simple-path? 2) How to handle case where attribute have no element. I have tried executing provided xsl file (in referred link) with xml files where some attributes are empty then after merging, such attributes ends without ending quotient.

XML:1

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="D:\UNISON\UniSON_Rel2\R&D\test.xsl"?>
<NCP>
        <NCPList>
            <NCP ID="1" Label="LabelName">
                <ParametersList>
                <MasterControl>Enabled</MasterControl>              
                <ReservedPool></ReservedPool>               
                <Rule ID="1" Label="Label">
                    <RuleCriteria>
                        <CellType>Macro</CellType>
                    </RuleCriteria>                 
                    <Assignment>Enabled</Assignment>
                    <ReAssignment>Enabled</ReAssignment>                    
                </Rule> 

                <Rule ID="2" Label="Label">
                    <RuleCriteria>
                        <CellType>Micro</CellType>
                    </RuleCriteria>                 
                    <Assignment>Enabled</Assignment>
                    <ReAssignment>Disabled</ReAssignment>                   
                </Rule>

                <Rule ID="3" Label="Label">
                    <RuleCriteria>
                        <CellType>Pico</CellType>
                    </RuleCriteria>                 
                    <Assignment>Enabled</Assignment>
                    <ReAssignment>Disabled</ReAssignment>                   
                </Rule>             
            </ParametersList>
            </NCP>
        </NCPList>
    </NCP>

XMl2:

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="D:\UNISON\UniSON_Rel2\R&D\test.xsl"?>
<NCP>
        <NCPList>
            <NCP ID="1" Label="LabelName">
                <ParametersList>
                <MasterControl>Disabled</MasterControl>             
                <ReservedPool></ReservedPool>               
                <Rule ID="1" Label="Label">
                    <RuleCriteria>
                        <CellType>Macro</CellType>
                    </RuleCriteria>                 
                    <Assignment>Disabled</Assignment>
                    <ReAssignment>Disabled</ReAssignment>                   
                </Rule> 

                <Rule ID="2" Label="Label">
                    <RuleCriteria>
                        <CellType>Micro</CellType>
                    </RuleCriteria>                 
                    <Assignment>Enabled</Assignment>
                    <ReAssignment>Disabled</ReAssignment>                   
                </Rule>

            </ParametersList>
            </NCP>
        </NCPList>
    </NCP>

XSLT:

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://ift.tt/tCZ8VR">
  <xsl:output method="xml" indent="yes" />

  <xsl:param name="aXmlPath" select="''" />
  <xsl:param name="aDoc"     select="document('q_xml2.xml')" />

  <xsl:template match="@* | node()">
    <xsl:copy>
       <xsl:apply-templates select="@* | node()" />
    </xsl:copy>
  </xsl:template>

  <!-- text nodes will be checked against doc A -->
  <xsl:template match="*[not(*)]/text()">
    <xsl:variable name="path">
      <xsl:call-template name="calculatePath" />
    </xsl:variable>

    <xsl:variable name="valueFromA">
      <xsl:call-template name="nodeValueByPath">
        <xsl:with-param name="path"    select="$path" />
        <xsl:with-param name="context" select="$aDoc" />
      </xsl:call-template>
    </xsl:variable>

    <xsl:choose>
      <!-- either there is something at that path in doc A -->
      <xsl:when test="starts-with($valueFromA, 'found:')">
        <!-- remove prefix added in nodeValueByPath, see there --> 
        <xsl:value-of select="substring-after($valueFromA, 'found:')" />
      </xsl:when>
      <!-- or we take the value from doc B -->
      <xsl:otherwise>
        <xsl:value-of select="." />
      </xsl:otherwise>
    </xsl:choose>
  </xsl:template>

  <!-- this calcluates a simpe path for a node -->
  <xsl:template name="calculatePath">
    <xsl:for-each select=".."> 
      <xsl:call-template name="calculatePath" />
    </xsl:for-each>

    <xsl:if test="self::*">     
      <xsl:value-of select="concat(name(), '/')" />
    </xsl:if>
  </xsl:template>

  <!-- this retrieves a node value by its simple path -->
  <xsl:template name="nodeValueByPath">
    <xsl:param name="path"    select="''" />
    <xsl:param name="context" select="''" />

    <xsl:if test="contains($path, '/') and count($context)">
      <xsl:variable name="elemName" select="substring-before($path, '/')" />
      <xsl:variable name="nextPath" select="substring-after($path, '/')" />
      <xsl:variable name="currContext" select="$context/*[name() = $elemName][1]" />

      <xsl:if test="$currContext">
        <xsl:choose>
          <xsl:when test="contains($nextPath, '/')">
            <xsl:call-template name="nodeValueByPath">
              <xsl:with-param name="path"    select="$nextPath" />
              <xsl:with-param name="context" select="$currContext" />
            </xsl:call-template>
          </xsl:when>
          <xsl:when test="not($currContext/*)">
            <!-- always add a prefix so we can detect 
                 the case "exists in A, but is empty" -->
            <xsl:value-of select="concat('found:', $currContext/text())" />
          </xsl:when>
        </xsl:choose>
      </xsl:if>
    </xsl:if>    
  </xsl:template>
</xsl:stylesheet>

Please provide help in above doubts.

Thanks in advance