to add to this... the following code works fine

use Win32::GUI;

$main = new Win32::GUI::Window(
        -name        => 'Main',
        -title        => 'temp',
        -width        => '325',
        -height        => '310',
        -minsize    => ['300', '310'],
        -style        => WS_OVERLAPPEDWINDOW,
    );

$main->Show();

$ok = "42";

$bitmap = new Win32::GUI::Bitmap("images/$ok.bmp");

push (@{$tmp},$main->AddLabel(
            -text => 'pic',
            -name => 'label_bitmap', 
            -top => '25', 
            -left => '10',
            -style => '14',
            -visible => '1',
            -background => [255,255,255],
            -foreground => [0,0,0],
            ));

$tmp->[0]->SetImage($bitmap);



Win32::GUI::Dialog();

sub Main_Terminate    { -1; }
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and this is very close to what happens in my program... the only difference is that i use subroutines...