Importing Into Custom Fields

Hello,

I am trying to import data into QAComplete. I have successfully done this using standard fields. But now I need to import some data into some custom fields which have already been created in the particular project. However, when I try to map the fields, none of the custom fields show up in the list.

I have tried looking around to see if this is possible, but have found nothing. Is it possible? If so, how do I get the custom fields to show up in the import mapping? If this is possible, I must be missing something simple...

Thanks in advance.