The *NEW* label will be added everywhere in your store, where the product is shown, i.e. at all pages (product, category, bestsellers, featured, latest, specials, search, compare, manufacturers, wishlist, specials page).
Just see the pictures from the Additional Images tab, and you'll get the idea

Installation is as simple as it can be, just open this, find that, after that add this, and it's done. No files are overwritten, no complicated database queries, no trouble at all.
If you need any help, free installation is on its way. Just contact me by leaving a comment, or via forum's PM (GoGo OpenCart).
OpenCart versions supported: All 1.5.x
Extension's page: http://www.opencart.com/index.php?route ... on_id=5069
