[Mediawiki-l] my Mediawiki installation is not rendering books

[Raymond M]

I had great help yesterday, so here goes today's question.

My mediawiki installation allows me to assign article pages to a Book,
save the Book, but not to download a .pdf or .odt

== MediaWiki 1.16.0 ==
2010-07-28

I have in my LocalSettings.php (yes, some commented out lines)

...
require_once("$IP/extensions/Collection/Collection.php");
$wgCollectionFormats = array( 'rl' => 'PDF', 'odf' => 'ODT',);
#$wgUseAjax = true;
#require_once("{$IP}/extensions/CategoryTree/CategoryTree.php");
#require_once("{$IP}/extensions/Book/Book.php");
require_once("{$IP}/extensions/PdfBook/PdfBook.php");
$wgGroupPermissions['user']['collectionsaveasuserpage'] = true;
$wgGroupPermissions['user']['collectionsaveascommunitypage'] = true;

When I am in the Manage Book I can add pages, see them listed as part
of the book, but when I click the download (either .pdf or .odt) the
browser screen goes blank.  I have made no attempt to move the
mw-render to the local machine, at least not so far.  My firewall and
port settings are just those per the Ubuntu 10.10 installation.

root at ubuntu1010servervm:/home/raymond# ping www.pediapress.com
PING www.pediapress.com (178.63.45.9) 56(84) bytes of data.
64 bytes from pediapress.com (178.63.45.9): icmp_req=1 ttl=53 time=177 ms
64 bytes from pediapress.com (178.63.45.9): icmp_req=2 ttl=53 time=179 ms
64 bytes from pediapress.com (178.63.45.9): icmp_req=3 ttl=53 time=178 ms

Perhaps there is a standalone .php script I can attempt to debug the
problem.  Or can someone point me to better instructions on the
mw-render installation.