Here is my site structure

What i am trying to achieve:

When i am on the "home-page" (level 1 i think) i want my navigation to show "welcome", "Navigation", "Content overview". These are all a documenttype called "startpara". If i navigate to one of these pages (go down one level) i still want the navigation to show these pages.

If i navigate from "home-page" to one of the other subpages e.g "eSourcing" (which is a documenttype called "modules") i want the navigation to show the subpages of "eSourcing". Again if i navigate to one of these subpages i still want the navigation to show these subpages. 

I hope that is understandable=:)

Here is the code i've got.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xsl:stylesheet [ <!ENTITY nbsp "&#x00A0;"> ]>
<xsl:stylesheet 
  version="1.0" 
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
  xmlns:msxml="urn:schemas-microsoft-com:xslt" 
  xmlns:umbraco.library="urn:umbraco.library" xmlns:Exslt.ExsltCommon="urn:Exslt.ExsltCommon" xmlns:Exslt.ExsltDatesAndTimes="urn:Exslt.ExsltDatesAndTimes" xmlns:Exslt.ExsltMath="urn:Exslt.ExsltMath" xmlns:Exslt.ExsltRegularExpressions="urn:Exslt.ExsltRegularExpressions" xmlns:Exslt.ExsltStrings="urn:Exslt.ExsltStrings" xmlns:Exslt.ExsltSets="urn:Exslt.ExsltSets" 
  exclude-result-prefixes="msxml umbraco.library Exslt.ExsltCommon Exslt.ExsltDatesAndTimes Exslt.ExsltMath Exslt.ExsltRegularExpressions Exslt.ExsltStrings Exslt.ExsltSets ">
<xsl:output method="xml" omit-xml-declaration="yes" />
<xsl:param name="currentPage"/>
<!-- Input the documenttype you want here -->
<xsl:variable name="documentTypeAlias" select="'StartPara'"/>
    <xsl:variable name="documentTypeAlias2" select="'Paragraphs'"/>
<xsl:variable name="cururl" select="umbraco.library:RequestServerVariables('URL')"/>
<xsl:template match="/">
<!-- The fun starts here -->
  
   <xsl:choose>
     
     <xsl:when test="$cururl='/home-page.aspx'">
       <div class="SideMenuColor">
        <ul>
     <xsl:for-each select="$currentPage/* [name() = $documentTypeAlias and string(umbracoNaviHide) != '1']">
          
        <li>
          <a href="{umbraco.library:NiceUrl(@id)}">
            <xsl:value-of select="@nodeName"/>
          </a>
        </li>
      </xsl:for-each>
       </ul>
     </div>
    </xsl:when>
<xsl:otherwise>
  <div class="SideMenuColorGreen">
  <ul>
  <xsl:for-each select="$currentPage/* [name() = $documentTypeAlias2 and string(umbracoNaviHide) != '1']">
        <li>
          <a href="{umbraco.library:NiceUrl(@id)}">
            <xsl:value-of select="@nodeName"/>
          </a>
        </li>
      </xsl:for-each>
  </ul>
     </div>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
</xsl:stylesheet>

This code only works as far as showing the navigation when i am at "home-page" and when i am on one of the pages with the documenttype "modules". 

As soon as i navigate to one of the subpages the navigation disappears because i go down one level.

What would be the best way to solved this issue? And please could you show me code examples?

Cheers.

Jan Molbech