It has to be something in the coding between 2.0.5 and .6. I can go back to .5 and all is well. 

Also, the error started showing on my 3rd server too. All three are back to 2.0.5 and doing fine.

P.S. config file follows.

{
  "Disable Ammo/Fuel duplication fix (Recommended false)": false,
  "Enable VendingMachine Ammo Fix (Recommended)": true,
  "Category Stack Multipliers": {
    "Attire": 1000000,
    "Misc": 1000000,
    "Items": 1000000,
    "Component": 1000000,
    "Ammunition": 1000000,
    "Construction": 1000000,
    "Traps": 1000000,
    "Electrical": 1000000,
    "Fun": 1000000,
    "Food": 1000000,
    "Resources": 1000000,
    "Tool": 1000000,
    "Weapon": 1000000,
    "Medical": 1000000
  },
  "Stack Categories": {
    "Attire": {
      "hat.wolf": {
        "ShortName": "hat.wolf",
        "ItemId": -1478212975,
        "DisplayName": "Wolf Headdress",
        "Modified": 1000000,
        "Disable": false
      },

It goes on to line 7190 and is 5,000 or so line too long for here.

I haven't gotten the error since i had grok fix it

Covfefe

I haven't gotten the error since i had grok fix it

You have multiple other issue if your using that code you posted, but if your that impatient go ahead and use it.

Thanks to the patient people i have found and fixed the proper issue, which is actually caused by items with water contents (smallwaterbollte, jug) when there added to a container and it tries to stack them