use FindBin qw($Bin);
# ...

$poe_main_window->configure(-title => 'Tor Monitor');
$poe_main_window->appname('TorMon');
$poe_main_window->iconname('TorMon');
$poe_main_window->optionReadfile(File::Spec->catfile($Bin, 'app-defaults'),
				 'startupFile');
$poe_main_window->configure
  (-background =>
   $poe_main_window->optionGet('TorMon.background', 'Top'));

##</code><code>##

! Main
TorMon.background: ghost white