Installation crash while installing system components.

Helo there...
I got Napoleon: Total War For My Birthday from my girl yesterday (I know right).
The only problem is that after I run the setup.exe and click on install napoleon total war it says "installing system components (vcredist i reckon) and after a while it throws me 2 errors at the same time:
1) "The system administrator has set policies to prevent this instalation"
The problem is I am the admin and user account control is turned off....
2) "Failed to run install script"
Dunno what that means.
I really need help as I've been looking forward to playing this game for a while now.....
I'll have to return the game if possible if no sollution can be found.
Please please please help me!

For one, try http://www.twcenter.net/forums/showthread.php?t=397636 on your C: drive icon, if not already done so.

For two, activate it on Steam.