I am not sure what the issue is with the monster milk truck (MMT)
demo.
I have tried the demo under Vista and Windows 7 using;
IE: 8.0.6001.18882
Plugin: 5.1.7938.4346
Everything seems to be working fine.
One thing you could try is using the developer tools in IE by pressing
F12 on the MMT page.
From there you should be able to go to the scripts tab and 'start
debugging'.
Hopefully it should give some indication of what the error is.
The other option is to try resetting IE to its default by going;
Tools -> Internet Options -> Advanced (tab) -> reset.
Hope that helps,
F.