PowerExchange for Salesforce uses up to version 50.0 of the Salesforce API for source and target transformations. To include Salesforce custom transformations, such as Lookup, Merge, and PickList in a mapping, you must use version 33.0 or below of the Salesforce API.
To use the latest version of the Salesforce API, create an application connection. You can also update the service URL in an application connection. To use version 50.0 of the Salesforce API, use the following Salesforce service URL:
https://login.salesforce.com/services/Soap/u/50.0
If a Salesforce object has a different structure than a previous version of the object, import the Salesforce object again. After you import the object, analyze associated mappings to determine if you need to update the mappings. Big objects are supported for source and target transformations.