Why zen-cart mods are not compatible with ZenMagick

The major factor is perhaps that most mods change core zen-cart core or template files. Since it is not required to isolate code and there is so much business logic in zen-cart templates, the user often ends up with pieces of PHP code that need to be pasted somewhere.

The alternative is that the code is burried in a distributed modified zen-cart template or module file. That makes it almost impossible to reuse files as they are. Usually it involves to extract the added code and wrap it in some nice functions.
Don’t get me wrong, there is nothing wrong with modifying core files. It’s just that usually the code is just bits and pieces that are hard to be used by other.

For me this is one of the major drawbacks with some of the mods. If you have other changes to the same file it’s virtually impossible to maintains all changes and keep track of updates.