I need a way of producing a gradient filled oval in a similar way to the square/rectangle.
I don't want to make graphics as the colours will be data driven and I don't want to make a series of seperate graphics and conditions to ensure the correct image displays, which will be very inflexable if the colour scheme changes.

I know that there is a simple transparency system, and I've got a 1bit bmp oval with the transparent area just fine. But I cannot get the duo-tone part to work. No matter what colour I tell it to display the black, it's always black when I preview.
The idea was then to tell it to display the black as white, and so produce the oval when placed over the top of a gradient filled rectangle.

The other idea I had was to use talk and a loop which draws progressively smaller filled ovals to produce something similar, but I'm having trouble working out how to do it.
This would be my preferred option, since then I can have this gradient filled oval sitting over another graphic to add fancy border to the oval.