The blue background was a quick fix for a blending issue resulting from forgetfulness. It doesn't particulary matter, however, as I was planning to do this with them:
Quite frankly, I find it scary that I just churned out a sig that's larger than a megabyte in size. People on this forum appear not to mind, however, seeing as they come up here all the time. Adding transparency to the mix would have resulted in either an even more horrendous file size or a very lossy sig, and i really didn't want to go there.
P.S. No, this was not done using ImageReady or some web site. Yes, I did have to manipulate the transpareny of several elements on each frame by hand.