Log into your account on Reallusion Homepage, select iClone 4 on Products Installed, and on right side is Bonus and Upgrade,The Auto-Driver Scooter is available to download.
I used to have iClone3 before upgrading to IC4.Both were on my computer and I found they don't mix and match. Used seperately they are ok,but try not to use scenes, avatars etc from one into the other.
Jimmy