I am getting the strange feeling that my undertaking of writing a "simple" script turns out to be a much larger project than I had anticipated.

Its not that much larger, its just that there is a lot of details :) Its like learning to sing in a new language, there is new sentence structure and new word list ... and you still have to practice hitting your notes :)(reading about it is different than doing it)

/bin/sh: gcc-4: Kommando nicht gefunden. Makefile:367: recipe for target 'Cwd.o' failed make: *** Cwd.o Error 127

Like Corion already said, looks like you're missing gcc-4 :)

Wide character in die at ... Path/Tiny. ... line 57 in the script

Isn't that wonderfully convenient? I think so (problem detected, error reported informatively)

So there is a problem with the filename, its got extra stuff. So, to solve the cause you work your way backwards, which function feeds RetrieveAndBackupXML? Which function feeds that function? Is it still called GetPaths? That is where you employ File::BOM, like

sub GetPaths  {
    use File::BOM;
##    my @paths = path( shift )->lines_utf8;
    my @paths = path( shift )->lines( { binmode => ":via(File::BOM)" }
+ );
    s/\s+$// for @paths; # "chomp"
    return @paths;
} ## end sub GetPaths
[download]

other way without File::BOM

sub GetPaths  {
    my @paths = path( shift )->lines_utf8;
    s/\x{feff}//g for @paths; # "de-bom"
    s/\s+$// for @paths; # "chomp"
    return @paths;
} ## end sub GetPaths
[download]

A tip: if you add use Carp::Always; you will get a stack of error messages, like

use Carp::Always;
use Path::Tiny qw/ path /;
sub f{g(@_);}
sub g { r( @_ ); }
sub r { path(shift)->lines }
f(666);
__END__
Error open (<) on '666': No such file or directory at C:/citrusperl/si
+te/lib/Path/Tiny.pm line 1469.
    Path::Tiny::Error::throw('Path::Tiny::Error', 'open (<)', 666, 'No
+ such file or directory') called at C:/citrusperl/site/lib/Path/Tiny.
+pm line 126
    Path::Tiny::_throw('Path::Tiny=ARRAY(0xabe0a4)', 'open (<)') calle
+d at C:/citrusperl/site/lib/Path/Tiny.pm line 740
    Path::Tiny::filehandle('Path::Tiny=ARRAY(0xabe0a4)', 'HASH(0xae824
+c)', '<', undef) called at C:/citrusperl/site/lib/Path/Tiny.pm line 9
+00
    Path::Tiny::lines('Path::Tiny=ARRAY(0xabe0a4)') called at - line 5
    main::r(666) called at - line 4
    main::g(666) called at - line 3
    main::f(666) called at - line 6
[download]