Alright, I'm not sure when or where, but at some point I successfully botched my ability to add categories. When I attempt to do so anywhere in my catalogue the admin window, after a long pause, displays the error:

Fatal error: Maximum execution time of 60 seconds exceeded in /home/cfestr2/public_html/cfecart/admin/includes/functions/general.php on line 232

...and it refuses to list the categories/products.

Upon closer inspection of the database, my new category was input with a category ID of '' (nothing), or 0. If a manually delete the entry it starts to work as normal again, but I still cannot create a category.

Hopefully I can simply repair this by restoring the file that contains the function that creates a category, which one is that? Thanks!