Transparent Issues

First of all may I say great job on the control!!!

I am currently working on getting my application to skin and look the way I want it. On all of my windows, I want to have a more rounded feel. I currently have the top caption's rounded, no problem there. I have tried to round the bottom corners on the main window and tool windows with little success. Right now, when you resize the window, the corners round but if you move the window you can see that the transparent is just the color that was directly behind it not a true transparent image. So if you move from a light background to a dark background you can really see the problem. The tool windows don't do transparent on the lower corners at all, I get a black image where the transparent color once was. Is this impossible to do or is there a problem with the control dealing with transparent images? I have noticed that none of the examples show rounded bottom corners, and maybe this is why.