Hi, I can't say what the hidden ramifications of this will do to your system, because the Busy method prevents any input while busy, but try this:

#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $mw = MainWindow->new();
$mw->geometry('200x200+500+500');

my $message = $mw->Label( 
 -text => "busy cursor test")->pack( -fill => 'x' );

#comment this block out for normal busy operation 
{
no warnings;
sub Tk::Widget::Busy{}
}

$mw->repeat(500, sub{ $mw->Busy });
$mw->repeat(600, sub{ $mw->Unbusy });

MainLoop();
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