Ultimately I had this issue as well.
There seems to be, for what ever unknown reason, rare cases that Circle Dock can not be installed and run properly from the Program Files or Program Files (x86)......It works like a charm from the program files (x86) on my desktop, but not on my laptop.
My solution was to do a clean install to a new folder I labeled; Program Files (Alternative)
This has had a lot of benefits, but 2 in particular.
1.) It is outside the UAC, but when Circle Dock is run, it is still monitored by the UAC
2.) This has given me a great place to put my self contained programs (ie. Portable applications or non-install)
I created the above mention folder, then did the Circle Dock install to that directory
I have not had an major issues since.
As I have pointed out this seems to be an intermittent issue with windows 7 64, but I am unaware of it effecting any ealier versions of Windows OS, and again it does not happen all the time. We are actively looking into this, but it is harder when it does not happen to everyone in the same manner across the same OS
Try it, if you are comfortable with doing so, and I'd bet good money it will work