While you can restrict what records come over based on ON record type (e.g. Students, Parents Employees, Alumni), with regards to the mapping of the fields on the record (such as any of the biographical, address, or employment fields), these mappings are hard-coded, and cannot be turned off.  Consequently, the user will want to make sure that the complete information is loaded in the Core record.

For more information on how the data integrates with ConnectRE, see Data Integration for Connect Raiser's Edge