How to import only featured image info without modifying anything else

I used the WordPress imported to import all the posts from the older server to the new server. However, the import file doesn’t include the featured image information, so I know it’s possible to export and import these settings using this plugin.

The problem is that after exporting the settings, I tried to import the information and it didn’t work, and the information from Media > Library page in WordPress has disappeared. It’s OK, since it’s a test site, but I need to figure the right steps to import the settings correctly.

So, my question is, what are the specific steps to import only the featured image information using this plugin? Also, what settings should I check and configure on Step 3 for images so I don’t modify anything else in the database other than featured image information. And what settings should I use on Step 4 to update existing posts without modifying the information already available in the database.

Thanks,