transparent panel - image

How I can put a panel with an image display that is transparent in some areas.

I want to make a cockpit like in the link. Any ideas?

http://i55.photobucket.com/albums/g157/micksaf/p51duw2.jpg

My favorite is:
Create a panel with a Bitmap with a alpa - cannel. (Example: *.TGA) You can create this Bitmap with Paint.Net or Gimp. Both Programms are free.

The other way:
Set all what should transparent to black(color 0,0,0) and set the OVERLAY flag from the Panel.

For this is an Example at the Workshop 4.

Widi. Thanks a lot! The answer was so simple...yet so complicated for a beginner.

So the sollution was to set the flags as bellow. Show or overlay

PANEL* first_pan =
{
pos_x = 200;
pos_y = 300;
layer = 1;
bmap = first_pcx;
flags = OVERLAY | SHOW;
}

well but i must say this is a double post!
Anyway, PNG files i like better, because it makes the alpha channel auto, depending on the back layer.. if using photoshop...