I've been using this plugin for a while now and love it, but noticed an incompatiblity with kagedesu's simple crafting plugin. When making more than one of the same object in the crafting scene, the quantity of crafting materials don't visually go down as they're used (they are getting removed though). Nothing comes out of the craft even after materials are used as well. This only seems to happen when this plugin is on. 
Would it be possible for you to take a look?
Viewing post in Ritter Active Item System (RPG Maker MV) comments
Hello, firstly thank you for your positive feedback. I'm sorry you're having this incompatibility, so far I've taken a look into this and found that the Ritter Active Item System ItemCore Compatibility.zip appears to be working alongside that crafting plugin. Try giving that version of my plugin a try and let me know how it goes. That version fixes an incompatibility with yanfly item core which had a similar issue of Cannot read property 'id' of null.
From my bit of testing I found no issues when crafting items using the ItemCore Compatibility version of Active Item System, granted I am not too familiar with this crafting plugin yet.
Let me know how it goes! Good luck and Thank you!
Edit:
As a side note: When I commented out my code which fixed the itemcore incompatibility it did indeed mess up this crafting plugin.