Here is a way to do it using XML::LibXML. Using Xpath expressions you should be able to match your nesting exactly. 
my $doc = XML::LibXML->load_xml(string => $xml);

my @nodes = $doc->findnodes('DatatoParse/elt');

for my $node ( @nodes ) {
    my $d1 = $node->findvalue('d1');
    my $d2 = $node->findvalue('d2');
    my @xnodes = $node->findnodes( 'Nest1/elt/Nest2/elt' );
    for my $xnode ( @xnodes ) {
        my $d5x = $xnode->findvalue( 'd5/X' );
        my $d5y = $xnode->findvalue( 'd5/Y' );
        my $d6x = $xnode->findvalue( 'd6/X' );
        my $d6y = $xnode->findvalue( 'd6/Y' );
        my $d10 = $xnode->findvalue( 'Nest3/Nest4/d7/d9/d10' );
        $d10 =~ s/^\s+//; $d10 =~ s/\s+$//;
        print "$d1,$d2,$d5x,$d5y,$d6x,$d6y,$d10\n";
    }
}

[download]
Output: 
TV show 1,Heroes,-2,-3,5,8,yipppeee
TV show 1,Heroes,-2,-3,5,8,yipppeee
TV show 1,Heroes,-2,-3,5,8,yipppeee
TV show 1,Heroes,-2,-3,5,8,yipppeee
TV show 2,Prison Break,-2,-3,5,8,yipppeee
TV show 2,Prison Break,-2,-3,5,8,yipppeee
TV show 2,Prison Break,-2,-3,5,8,yipppeee
TV show 2,Prison Break,-2,-3,5,8,yipppeee
TV show 4,Alias,-2,-3,5,8,yipppeee
TV show 4,Alias,-2,-3,5,8,yipppeee
TV show 4,Alias,-2,-3,5,8,yipppeee
TV show 4,Alias,-2,-3,5,8,yipppeee

[download]

In reply to Re: Parsing a highly nested XML file correctly and efficiently by tangent
in thread Parsing a highly nested XML file correctly and efficiently by Ppeoc

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