Plain Jane AmigaOS has no support for Alphablended Gadgets.
But I am wondering if P96 or CGX does support that?
I can't imagine that it would be possible since the alphablending would alter the background in unpredictable ways.
My GfxMage wants my AmigaOS Gadgets to cast shadows on 16M Color Screens. To this end he has added several pixels of Alphablendiness to the gadgets.
I already told him that I didn't think it could work.
But I wanted to get a definitive answer from one of the experts lurking about on the org