It was basically working with one weird crafting issue yet to be resolved, but I never got a response as to which approach we should take regarding storing extra metadata.
 
 could you have a look at it?
 
"I never got a response as to which approach we should take regarding storing extra metadata"
 
I think the Json way makes the most sense for us.
 
If I have some time again I'll have another look and submit a pr.