First, make sure you have Win32::GUI version 0.0.558 installed.

Second, check if this script bombs (it shouldn't):

#!/usr/local/bin/perl -w

use strict;
use Win32::GUI;

my $winMain = new Win32::GUI::Window(
        -left   => 13,
        -top    => 32,
        -width  => 439,
        -height => 260,
        -name   => "winMain",
        -text   => "Autoscroller"
        );

my $btnTest = $winMain->AddButton(
        -text    => "btnTest",
        -name    => "btnTest",
        -left    => 0,
        -top     => 0,
        -width   => 60,
        -height  => 20,
        );

$winMain->Show();

Win32::GUI::Dialog();
[download]

Your error sounds exactly like the well-known "no -name option" problem, which is present in some of the examples in the Win32::GUI tutorial :/

All windows and controls need a -name.

/J