In models > orders.model.php, in the formatReportRow() function, the line in the foreach() loop that reads:
$formatted_row[$text] = $row[$name];
$formatted_row[$text] = $row[str_replace(" ", "_", $name)];
Otherwise, the returned $formatted_row will contain blank values for any $row element that has an underscore in the name, e.g. "ship_address".
I do not know whether the line above that that reads
$formatted_row[$k] = $v; must be changed as well, because I do not go through that line of code with my Settings and have not tested it.