#!/usr/opt/perl5/bin/perl -sw

use XML::Twig;
my $twig = XML::Twig->new();
$twig->parsefile($xmlfile);
my $root = $twig->root;
foreach my $i ($root->get_xpath('substring(//OLifE/Party[@id=//OLifE/Relation[RelationRoleCode/@tc=8]/@RelatedObjectID]/Person/First
Name, 1, 30)')) {
   print $i->{att}->{InvType};
   foreach my $j ($i->get_xpath('../InvCounts/InvCount')) {
      print " " . $j->{att}->{Count};
   }
   print "\n";
}

##</code><code>##

./twigs.pl -xmlfile=a2b9f375-51fe-41a1-86ab-069561517890.xml
error in xpath expression substring(//OLifE/Party[@id=//OLifE/Relation[RelationRoleCode/@tc=8]/@RelatedObjectID]/Person/FirstName, 1, 30) around substring(//OLifE/Party[@id=//OLifE/Relation[RelationRoleCode/@tc=8]/@RelatedObjectID]/Person/FirstName, 1, 30) at ./twigs.pl line 7