I got it to work that way but only with a baretext filehandle and without using strict. When I used a lexical variable I got the error message "Can't use an undefined value as a symbol reference at D:\Users\lock\t2.pl line 18." Line 18 is the print statement.

I still don't understand why the tie didn't work. There was no implementation of TIESCALAR in the module but I found TIEHANDLE.

#use strict;
use warnings;
use Data::Dumper;
use Win32API::File 0.08 qw( :ALL  );

my $testfile = "test.xml";
print "file exists\n" if -e $testfile;
my $hObject = createFile( $testfile, 'rw k e' );

unless ( $hObject ) {
    die "error creating handle: $^E\n";
}
print Dumper( $hObject);

my $fh;
OsFHandleOpen( FHTEST, $hObject, 'rw' ) or die "OsFHandleOpen: $^E\n";

print FHTEST "test";

print "finished\n";

__DATA__
output:

Name "main::FHTEST" used only once: possible typo at D:\Users\lock\t2.
+pl line 18.
file exists
$VAR1 = 116;
finished
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