SDO DAS XML "drops" some elements

Hello, I try to generate a XML using an XSD with the library SDO DAS XML: http://www.php.net/manual/en/book.sdo-das-xml.php Most elements are working nicely, but others are just missing in XML. There where no warnings and no log entries. Where can I get some more debug information? Is there a more detailed tutorial somewhere? Are there any known bugs in that library? Thanks for any help Emil