WOW! I never thought ZenCart and it's parent, OSCommerce, could ever be redeemed. These are great products with really unpleasant code. Hacking these apps is a nightmare.

Now, someone's come along with a big replacement to ZenCart called ZenMagick. I just skimmed over it, and the code is much better. The product attaches to ZenCart and exposes and OO API to the underlying database.

It's an MVC framework, so it takes some time to grasp what's going on, but after that things should get a little easier.

There are some things I thought were lame, like the class loader, which limits the amount of subclassing you can do, but you can get around that.

This is a really interesting project, because it's attaching itself to ZenCart, and can potentially fork it and take it over. While there are a lot of OSC and ZC plugins, the app is hobbled by the complexity of installing these plugins.