Hey kim!
When exporting with migrate db, afaik you only export 1 file which is a gzipped sql file. Or just a sql file.
Should look like this:
db2597341-migrate-20160827085604.sql
or
db2597341-migrate-20160825173231.sql.gz
This line of text contains all Customize settings. Search for the word "pa_icon" and find some text that looks like: "pa…
What you are referring to here only applies if everything worked but your customize settings are lost after you imported the database. Actually this is a pretty rare case, but I had this problem once.