I'm not sure what the problem could be (and I don't have a windows perl available at the moment) but this works for me on linux: 
use strict;
use XML::XSLT;

my $xmlFilename = '/home/joost/input.xml';
my $xslFilename = '/home/joost/input.xsl';
(my $outFilename = $xmlFilename) =~ s/\.xml$/\.csv/i;

my $xslt = XML::XSLT->new($xslFilename, warnings => 1);
$xslt->transform($xmlFilename);
print $xslt->toString;

[download]
Can't help you much further than that, though.

update: did you update the XML modules, or where they already at the latest version?

You can check by doing 

perl -MXML::XSLT -e'print "$XML::XSLT::VERSION\n"'

[download]
and similar for XML::Parser
"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re^3: Using XML::XSLT to convert XML to CSV by Joost
in thread Using XML::XSLT to convert XML to CSV by Photius

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