NPC Merchant Stackable Item Bug + Itemforge 'Tradeable' Option?

[Northman 18]

Hello Epsi Team!  -> Video of me explaining the issue if you don't wanna read; https://streamable.com/uwa0sc

There's two things I want to mention in this forum post. 

1. When you create an NPC merchant that sells items in stacks, it breaks after first use. So the first time you add the item to the merchants wares, you can buy it in stacks. The moment you close the merchant window and re-open it, it no longer allows ANYONE to do this. Not me, not my alt, not my friends. Completely stops giving the option to buy items in stacks when you hold L-Shift + Right Mouse Button. Tried relogging, tried recreating an item, tried it with both custom and in-game items. It no workie after one try. 

2. I'm trying to make a custom currency in my phase to make it more immersive. I called the custom currency 'Lumin'. I specifically made an additional custom item called a 'Lumin Cheque' which will be used to buy Lumin coins. This way I prevent people from buying Lumin with regular gold and silver, since people have access to infinite gold on the server through the .mod money command. 

Problem is, if I want players to be able to use the Lumin coin and the Lumin Cheque to purchase wares in the phase, I need to give them access to be able to .add the item. Now obviously that would bring me down to the same path. If players are just able to .add item #infinite amounts then the whole idea won't make much sense since the coin will be worthless. 
 

My point if you are in a hurry -> Is it possible to have a command where players can "use and consume" a custom item (purchasing things in this case), but not be able to create it themselves?

 

Please let me know what's possible here! 

Thank you very much for your time! ♥ 

Kind regards, 

Turkish Dad 
Discord; turkishdad