Step 12: Turn On Center Box Tabs:

In your zen cart admin go to Configuration -> Index Listing

Click on "Show New Products on Main Page" select a value greater than "0" and click on the "update" button.

Repeat the above steps for "Show Featured Products on Main Page" and "Show Special Products on Main Page".

See these tutorials for more detail:

Easy Help Tutorial: How to Add New Products to the Main Page

Easy Help Tutorial: How to Add Featured Products to the Main Page

These boxes will not show until you have created Featured Products and Specials. See these tutorials for instructions on creating Featured Products and Speicals in the zen cart:

Easy Help Tutorial: How to Create a Special for a Product

Easy Help Tutorial: How to Create a Featured Product

The New Products centerbox will not show until you have added products to your store. See this for setting which products show up as new:

Easy Help Tutorial: What Determines if a Product is "New"