Changing a Tree Walking, forward walk example

I am having trouble converting this Tree Walking, forward walk example :
http://www.dpawson.co.uk/xsl/sect2/N4486.html#d6060e1105

Into something more related to my problem and I am using XSLT 2.0.
The example in mention will convert this:

<document>
 <para>First para</para>
 <change-start id="c1"/>
 <para>Second para</para>
 <para>Third para</para>
 <change-start id="c2"/>
 <para>Fourth para</para>
 <change-end id="c2"/>
 <para>Fifth para</para>
 <change-end id="c1"/>
 <para>Sixth para</para>
</document>

<document>
 <para>First para</para>
 <ins id="c1">
   <para>Second para</para>
   <para>Third para</para>
   <ins id="c2">
     <para>Fourth para</para>
   </ins>
   <para>Fifth para</para>
 </ins>
 <para>Sixth para</para>
</document>

<document>
   <p>Non List text</p>
   <list>
       <li>First item</li>
       <li>Second item</li>
   </list>
   <list>
       <li>First item</li>
       <li>Second item</li>
       <li>Third item</li>
   </list>
   <p>Unrelated Text</p>
   <p>Not in a list</p>
   <list>
       <li>First item</li>
       <li>Second item</li>
   </list>
   <p>More Unrelated Text</p>
   <p>Not in a list</p>
</document>