Rather weird GUI problem

[Codein]

I've having a really strange problem with setting a custom gui bitmap.

I'm using a 24-bit PNG with transparency.

This is the code I'm using:

PHP Code:

//#CLIENTSIDE

function onCreated() {
  Message_Window.destroy();
  
  new GuiControlProfile("MessageWindow") {
    bitmap = "guiquian_messagewindow.png";
    transparency = 0.5;
  }

  new GuiWindowCtrl("Message_Window") {
    profile = "MessageWindow";
    x = (screenwidth - screenwidth) + 180;
    y = (screenheight - screenheight) + 20;
    width = screenwidth - 200;
    height = 100;
    text = "message bar";
    //No Control
    canresize = 0;
    canclose = 0;
    canmove = 0;
    canmaximize = 0;
    canminimize = 1;
  }
 
} 


I've attached the image I've used and a screenshot of what's going on.