Mapping a SKU to a campaign
C&P makes it easy to automatically assign any opportunity created from a transaction to be assigned to a specific Salesforce campaign.
Navigate to C&P Settings -> Opportunity
Scroll to the bottom of the page
In the bottom section you can Assign the campaign to your sku by several criteria. Note it has a fancy lookup feature so you can just start typing the name of your campaign and it will autocomplete with the Salesforce ID for you automatically.