Glad its working for you D-vious but I've already tried running in Vista compatability mode and as admin. But its still no go for 64-Bit mode (I did wonder if I was mistakingly running Windows 7 32-bit instead of the 64-bit version but have confirmed that this is not the problem - even I'm not that dumb
).
On Vista I can now run the 64-Bit version at 1920x1200 (provided I run the 32-bit version first). However this hasn't worked with Windows 7.
Indeed if I try and run the 64-bit exe after running the 32-bit exe I get an "application failed to start" error.
Oh well booting into Vista instead of Windows 7 to play CWH isn't too much of a hassle