I don't use MS Windows so can't judge the effectiveness of your script. This is just a comment on a couple of lines of your code.

  my $paths = join "\0", @_;
  $paths .= "\0\0";
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They could be condensed into one statement.

  my $paths = join "\0", @_, "\0";
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An example

johngg@aleatico:~$ perl -Mstrict -Mwarnings -E '
my @p = qw{ a b c };
my $p = join "\0", @p, "\0";
print $p;' | hexdump -C
00000000  61 00 62 00 63 00 00                              |a.b.c..|
00000007
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I hope this is of interest.

Update: Corrected typo slash to backslash, thanks to all who pointed it out.