Hi,

you will need an internet connection, but you don’t have to have it on your studio computer. When you launch EZdrummer, you will get prompted with the Authorization screen. Write down the computer ID that is given to you, then go to a internet connected computer. Log on to your account and go to My Products and your EZdrummer page (if you haven’t registered your serial #, now is the time to do it). Click Add authorization and write the Computer ID that just just wrote down. Then add a computer description (Studio iMac or whatever you’d like) and proceed. Then write down the authorization code you are given, and go back to your studio computer and fill in the authorization code. Done!

The process is also shown in this video: http://www.toontrack.com/support/?prod=EZdrummer%20and%20EZX%20expansions&issue=Authorization&os=Other&seq=Other&ID=13