1) Once you startup the Reallusion program, click "Sign me up!" on the "SIGN UP NOW AND GET" screen.
IMPORTANT: During the very first time you use the program, please do not skip the "SIGN UP NOW AND GET" screen by checking "Do not show again", as this is a way to register your product in order to get the bonus content.
2) Then, another screen will be pop-up for you to register or create your account. Please Register it accordingly. This will automatically register your product under your login.
If you are a new Reallusion member, click "Create Account" button to register as a new member.
3) After product registration, login to the Reallusion member page.
4) Go to the "Registration" page, then select your product's "Download".
5) In the Product Information page, you can find the bonus downloads section for the product you purchased. You may click the download link accordingly.
6) It is recommended to save the bonus content installer for future re-installation, since the bonus content will be overwritten once the Mac App Store updates the application.