Problem: Country list automatic fill in feature missing countries

Summary: We need to have respondents identify their country. I created a question with drop-down list, then used the automatic fill feature and selected “fill with” “countries.” The resulting list seems to be missing countries, and has some errors in the list. How can it be corrected? I can manually add the missing countries to the end of the list, but then they are out of alphabetical order. And adding after some responses means data will be segregated into two.

Is there a way to add in the missing countries (Afghanistan, Burma/Myanmar, so far…) after some responses have been collected, WITHOUT having the responses broken into pre-edit and post-edit groups?

Thanks.