Ok, so what you are saying is that the radio box gadget is rendered black because the window doesn't use transparency?
This doesn't make sense to me, and I tried to change the transparency on both the gadget and the window, no difference (except the window became transparent).
edit,
Now that I look at the screenshot in the first post, i can see that it may look like the window is transparent, and this is the cause of the "transparency problem".
But it's just a photoshopped image in order to better visualize the problem.
So forget anything about transparency, as I haven't used it in my application, and am not going to use it.
edit2,
I tried to run the application without the winXP Look, and now the black stuff is gone (in win98 style), if I switch back to XP look the black stuff appear again. (I'm talking about the manifest file that transforms the app. into winxp look)
I allways afraided from a clowns. aww..