You can order the items by descending order, so the categories will be sorted by newest at the top and oldest at the bottom. To do this, go to your menu.php page in the CSSMenuWriter/cssmw_home/ directory within your powerstore and find the MySql query that looks like this:
"SELECT CategoryName, CategoryID FROM productcategories"
Change it to look like this:
"SELECT CategoryName, CategoryID FROM productcategories ORDER BY CategoryID DESC"