CMN fails with "The file to import, '<filepath\filename>', does not contain the required field(s)" (4248663)

Attempting to import a resource map in Coexistence Manager for Notes (CMN) via the 'Mail Connector | Resource Mapping | Import from NME…' button fails with the following error:

The file to import, '', does not contain the required field(s)

Generate the import file in the Notes Migrator for Exchange (NME):

 View Summaries | User and Resources Details | View Summary… | Export to TSV…

If trying to use the 'SmtpAddressResourceName' format, select the file with the '…' button, which precedes the 'Import from NME…' button.