There is a whole lot of built-in stuff that’s not very obvious when starting out, and I’m afraid that quite a lot of it will conflict with what you’re trying to do with this extension. (As an example, your post at Removing "a" or "an" From Inventory List - #6 by Sunroses – this is happening because the standard code sees a singular object.)
It seems like in essence what you want to do is try to create single objects that act as quantities of objects, but it’s not clear why you want this approach over making multiple instances of new kinds. If you describe what you’re trying to achieve at a higher level, someone might be able to offer better advice.