"One of the requirements for the installation of CFT under Win2008 is the deactivation of the UAC. CFT would be the ONLY software used by us which has that requirement and will be unusable for us if this requirement is continued. The deactivation of the UAC has been expressively forbidden by our IT Security and is not negotiable.

Why must it be disactivated? Is there any way to install CFT on Windows 2008 with UAC active?

To install our product in service mode,  users need some specifical rights. Otherwise there will be a pop-up appeared during installation indicating the error. Synchrony installer does not handle this pop-up and will run into trouble.
So for the user who has all necessary rights for installing the product in service mode, he does not need to disactive UAC. And for running CFT after installation achivement, the UAC can be re-activated if it is disactivated.