Did you check this out? http://blog.david.connolly.name/2006/09/elgato-eyetv-hybrid-in-windows.html
So maybe it is possible. I'm reluctant to repeat what I've already done, but maybe I'll give it another go from Boot Camp once it's set up. If I fail again, then I'll go for a dedicated PC stick. I will be needing two sticks anyway, one for my wife and one for my new iMac.