Aah - yes - I had not read that file down ... thanks.

Also - these (completely incorrect) loops:

FILE:
while (my$file = @files) {
    for my $kp (@KEEP) {
        next FILE if $file eq $kp;
        
    }
    rmtree($deletes);
}
  return;
}
[download]

can be written in a more perlishly as :

my %keepers = map {$_=>1} @KEEP ; # OR declare %KEEP instead of @KEEP
rmtree ([grep {not $keepers{$_} }@files]);
[download]

(untested).

You probably need to chomp(@files) too, before this operation.

File::Path documentation prefers remove_tree over the legacy rmtree.