EDIUS 6 or ealier used USB KEY to confirm proper license. Instead of this, EDIUS 6.5 uses serial number activation that registers a serial number to the license server.
There are two ways to make activation. One is for a PC that is connected to the internet, and another is for an offline PC.
For a PC that is connected to the internet
Registration dialog box will appear when you launch EDIUS for the first time. Enter your serial number to the dialog box.
For an offline PC
You have to prepare another PC that is connected to the internet, and you also have to prepare thumb drive or something to move data files between both PCs. Please read the Edius Installation Guide for further information.