Please let us know the problem you are facing? Have you checked our getting started guide from knowledgebase? Our knowledgebase has all the resources that will help you get started with the powerful and flexible features that Pro has to offer.
Cornerstone is already integrated in Pro theme. Simply go to Pro > Launch and you will see the Three Options, Templates, Header, Content and Footer. When you click on the content, this is the content editor which is using Cornerstone.