The following code still seems unresponsive (can't click on button, and label is not refreshed). This must be a windows thing.

use Tk;
use IO::Socket;
use strict;

my $sock;
my $port = 7076;
my $time = 60;

my $mw = MainWindow->new;
my $button = $mw->Button(-text=>"click",
             -command=>sub{exit;})->place(-x=>0,-y=>0);
my $l = $mw->Label(-text=>"$time")->place(-x=>0,-y=>50);

$mw->update;
$sock = new IO::Socket::INET (
                  LocalHost => 'localhost',
                  LocalPort => $port,
                  Proto => 'tcp',
                  Listen => 1,
                  Reuse => 1,
                  #Timeout => 0.1,
                 );
die "Could not create socket: $!\n" unless $sock;
$mw->fileevent($sock,'readable',[\&readit]);
$mw->repeat(100,sub{$l->configure(-text=>$time--);$mw->update;});
MainLoop;

sub readit{
  my $new_sock = $sock->accept();
  my $in = <$new_sock>;
  print "received $in\n";
}
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