hmm

[Gibbs]

I know absolutely nothing about W7, but I've had loads of similar issues between XP and Vista, and usually they were removed by using the Compability mode option, where you can choose to run it as an older version would. I don't know if W7 even has this possibility anymore, but you can give it a try ;D
You can put the run as administrator funtion to automatic aswell (it will ask you before you open the game though).