We have a standalone product (not browser based) that uses Flash for some of its gui. We let flash render to a windowless control then used that bitmap as a 3D texture where it is then displayed by directx
we have traditionally taken advantage of the 'render it on black, then render it on white, and painfully extract the alpha info from the flash movie' since we need the full alpha from the movie.
As of flash 11, no matter what we prefill the bitmap to (and we use wmode=transparent), flash now overwrites that with black, preventing us from extracting the alpha and leaving ugly black outlines everywhere.
While it would be great if Flash wmode=transparent just started working again, what would be even more fantastic would be if we could use wmode=window and have flash directly provide the alpha into our target render bitmap.
Better for flash, better for us. But as far as I can see, the Draw() method only ever renders RGB and not RGBA
It seems that the same problem had f-in-box, but it seems that they've resolved it. Here a customer writes about "black background" problem: http://f-in-box.com/forum/viewtopic.php?t=873. After some time new update is issued where it fixed: http://f-in-box.com/forum/viewtopic.php?t=891
Hope it helps.