Shaped Windows Forms and Controls in C# .NET

Question

I followed the instructions MSDN suggests as far as creating a custom-shaped form. You can find the write up by going to: Shaped Windows Forms and Controls in Visual Studio .NET If you happen to actually read it, you'll notice it says, "Monitors set to a color depth of greater than 24-bit can display problems with certain parts of the form not being transparent, despite setting of the TransparencyKey property. To avoid this problem, ensure that the monitor's color depth is set to less than 24-bit in the Display control panel. When developing applications that feature this transparency, keep in mind that you will have to make your users aware of this issue." Well, they weren't fooling anyone. I'm current viewing at 1280 x 1024 @ 32-bit. When my display settings are 1024 x 768 @ 16-bit (24 not available) my image actually seems transparent but with a noticable reduction in image quality. My question is, how does Microsoft get WMP9's background to be transparent? GDI+? I'm unfamiliar with GDI however very eager to learn if anyone has any great tutorials on the web. I scanned the forums and came up short. That link was actually provided by someone else who wrote a tutorial on the very subject. Thank you in advance. Matt