Don’t worry, Auto ads support is included in the basic version of Advanced Ads.
Enabling Auto ads with Advanced Ads is quite simple. Just go to _Advanced Ads > Settings > AdSense_ and enter your Publisher ID (you can find it in any URL when you are logged in your AdSense account).
Now, enable “Verification code & Auto ads” and save the settings.
This will place the Auto ads code automatically in the right position in the header.
Depending on your AdSense account status it might not deliver ads right away, but you can let me know after you enabled the option and I can check your site if the code was added properly.
Thomas