As simple as this:
$rows = get_field('repeater' ); // get all the rows
$specific_row = $rows[YOUR_ROW_NUMBER]; // 0 will get the first row, remember that the count starts at 0
$title = $specific_row['SUB_FIELD_NAME']['title];
In your specific example the SUB_FIELD_NAME would be downloads_acf_field_single_product
