Import Feature Images

Hi, I’m trying to implement Directorist, and have spreadsheet of several thousand companies to import. I can see the field to bring in Images (just general images to appear in the profile) but struggling to see how to import the all important Featured Images.

These are key because (my understanding) is that these are the images which appear all across the site, in search results etc.
What am I doing wrong?

2. A follow-up question: Why are company profiles duplicating when I re-upload them? I would have expected a NEW / UPDATE process, where you can check if it needs to update an existing profile first before creating new.
What am I doing wrong please?