Disclaimer - Lets clarify a few things:
I'm doing this for me, then sharing it with you.
There is no warranty or guarantee that any of this will work for you or your site.
Accept that there are many other ways to code similar features into a free open source php e-commerce site, I'm aiming to make it work with as much clean coding as possible.
Line numbers are to ZenCart like an analog compass is to someone that's lost.
If my work has helped you today in any way, show your appreciation with things like positive feedback or donations.
I'm for hire, not for sale.