mb> XML is verry strict. Either you have a valid XML file, or you dont.

 JV>     How do you check validity?

Your XML parser does. You can choose to just check the validity or you can
confirm the structure against a pre-defined schema.

 JV>     Invalid data in one line do not necesserily mean that the
 JV> entire file is invalid.

In XML, it does.

 JV>     I want to know who or what are the top levels you meant and why
 JV> you considered to start from them (which or whatever they are).

When it comes to the nodelist, it would be quite enough to let ZC keep the
base XML file maintained. Perhaps a new util for this would have to be
developed. But thats all.

To start anywhere else (ie at node level) would only create a lot of
confusion and problems.

//Micke 
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