Seeing that there is a mass of questions about the SSE2 issue, can the Moderators re-post FruitFly's advice heading it up as something like:

"M2:TW Demo and SSE2"

I think it would be handy to have something posted specifically stating this and pointing out that this may not be an issue in the finished game.

.....fingers crossed for those without 64-bit processors.

Personally I can't run the game at all. I need a complete new system anyway, so I haven't lost anything