The Skills and Experience Mapping area links to the Qualifications section on the Constituent’s Volunteer tab.

Below, you can see a screenshot of the Skills and Experience Mapping section of Importacular.

Here are the area settings for this mapping:

You should select what fields you would like to be used to determine a match to the Raiser’s Edge as well as what you want to happen when there is a match (add anyway, update RE or leave RE as is).