Color wheel user Jim wrote in to say that he was having trouble with the transparent shading square in both FireFox 1.0.2 and Internet Explorer 6. I couldn’t replicate the FireFox problem, but my IE at work is doing the same thing. More breakage from the perpetually broken browser is frustrating, to say the least, but you can still use the shading box without the color background (while you’re waiting for a real browser to download).
So if you want the geeky explanation, here it is: I use a directX thingamajig (DXImageTransform.Microsoft.AlphaImageLoader filter) to get around IE’s fundamental brokenness as it manifests itself in PNG transparency. The latest service pack (SP2) seems to have turned off directX stuff for some people, which is, I suppose, what I get for using stupid proprietary extensions to broken browsers.
If you’re interested in stupid proprietary extensions for your antique broken browser, here are some other links about PNG alpha transparency support:
Or just use FireFox.