you're right, it would look like crap. My theory was to try to render
a tga foreground animation in the image property of the picturebox and
a background (non transparent) in the background image property of the
picturebox. this is just because sometimes we run multiple passes on
shots and composite them up afterwards, so it would be good to preview
this before we send them to after effects. Since we normally
premultiply the background pixel color into the fg on composite it
probably wouldnt look great without that anyway, as you end up with a
black or white halo aroung the edge where the alpha overlay is.
anyway, the main thing is playback performance and i have that with
your library over any other.

at the moment for non transparent tga and jpg sequences i'm just
loading the file from IO_loadimage and converting and returning a
bitmap into an image collection. It is very fast to cache these and
the picturebox refresh is bound to a timer that fires 25 times a
second. it plays back realtime at the moment after about 5-10 seconds
of caching so i'll probably stick with it. it's better than what my
£3000 3d software can manage!

cheers!