You could use something like Beyond Compare from scootersoftware.com and see if you can locate where the differences between v1.3.0.2 and your site are ...
Or, backup your whole site ...
Get a clean download of the Full Zen Cart v1.3.0.2 download from the link above for get Zen Cart ...
First, try to Reload:
/includes/modules/category_row.php
Does it work?
Next, Reload all of the directories and files in the:
/includes/templates/template_default
Technically, these files should never of been touched ...
Does it work?
NOTE: be sure you have a complete backup of your site before you get started ...
You could try a slower method of updating files by looking at the dates and times and see how they compare, but unless you are pretty familar with your site and how the dates and times vary, this could be more trouble than it is worth ...