Add to your index.php
Create a new column on download table and past this
Code:
<?=(date("d/m/y") == date("d/m/y", $dl['dat'])) ? 'Today' : (date('d/m/y', mktime(0, 0, 0, date("m") , date("d") - 1, date("Y"))) == date("d/m/y", $dl['dat']) ? 'Yesterday' : date("d/m/y", $dl['dat']))?>