This was only published on 30th September 2011, following the re-opening of the Inquiry with further information being made available to the Coroner.
This pointed at the GPS being non-functional as the cause of the aircraft being some 11NM off-track.
6 deaths
Some reading is at: http://www.dicksmithflyer.com.au/article_322.php
and the Coroner’s report is at: