I can't integrate portable TeraCopy as default copy program

I want to install TeraCopy in portable format and during installation i choose Portable Version, but after this in the Preferences window it doesn't allow me to select Use TeraCopy as default copy handler. Image: http://img850.imageshack.us/img850/6886/7lki.jpg (http://img850.imageshack.us/i/7lki.jpg/) Can someone tell me how to integrate portable TeraCopy in Windows and make it default...