You might want to print newlines to force printouts....you may be suffering from buffering.

 $monitor->watch( {
        name        => 'C:/Path',
        recurse     => 1,
        callback    => {
            files_created => sub {
                my ($name, $event, $change) = @_;
                print "@_\n callback fired \n";    #will print right a
+way, (on linux anyways) 
            }
        }
    } );
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