If you want to use atitool, then install JUST the display driver and the VIVO drivers, then everything will work fine, but when you go to control panel->Display->Advanced, then there will just be some generic tabs. This is because CCC hasnt been installed as the interface to the extra options.
This is where you install the newest version of whatever 3rd party tool you want to do your tweaking ie. Atitool/Ati Tray Tools/Riva tuner. That should sort it out.
As a side, I am using these drivers with 6.7 and i think that they are getting the memory usage and startup times lower, this is -
IMO - the best release since 6.3 and its great for OGL too now, as Prey has shown me...
IQ is subjective as ever, but I'm not looking for errors. If it runs fine then it all good...