Explanation
The order of uploading Salesforce objects during an FSC data migration is important to ensure data integrity and avoid errors. The recommended order is:
Accounts and contacts: These are the core objects that store the basic information about the customers and their relationships. They should be uploaded first to establish the foundation for the FSC data model4.
Financial accounts: These are the custom objects that store the financial information about the customers, such as balances, interest rates, fees, and transactions. They should be uploaded after the accounts and contacts, and linked to them using lookup fields5.
Account groups and households: These are the custom objects that group the accounts and contacts based on common attributes or relationships, such as family members or business partners. They should be uploaded after the financial accounts, and linked to them using junction objects6.
References:
Financial Services Cloud Data Model
Data Migration Best Practices
Accounts and Contacts
Financial Accounts
Account Groups and Households

Explanation
The following things happen when an opportunity record that has opportunity participants with associated share table entries is set to Private:
The share table records are deleted, which means that any sharing access granted by the opportunity participants is revoked.
The opportunity participant records are not deleted, which means that they still exist on the opportunity record and can be viewed by users who have access to the opportunity.

Explanation
To ensure the data is loading into the correct fields in Financial Services Cloud, the consultant should utilize a field mapping file with the external system allocation and the corresponding field in Salesforce. A field mapping file is a file that specifies how fields from an external system map to fields in Salesforce. By using a field mapping file, the consultant can ensure that the data from the new custom object is imported into the correct fields in Financial Services Cloud and avoid any data loss or inconsistency.