Soon as I turn off simple mode, I get the new large config file.  Download it , I change any value under

Failed to call hook 'OnServerInitialized' on plugin 'BlueprintManager v2.0.6' (ArgumentException: An item with the same key has already been added. Key: -1478212975)

I even reuploaded the plugin from scratch and downloaded the generated config, turned on advance mode and reuploaded the file without any changes and still got the error.

Makes me think item duplication somewhere in the generator json ? 

Same here, deleted the config and unloaded the plugin and then reloaded the plugin to generate a new config.

And this is the error it gives in the console:

o.reload BlueprintManager
Unloaded plugin Blueprint Manager v2.1.4 by Whispers88
Failed to call hook 'OnServerInitialized' on plugin 'BlueprintManager v2.1.4' (ArgumentException: An item with the same key has already been added. Key: -1478212975)
  at System.Collections.Generic.Dictionary`2[TKey,TValue].TryInsert (TKey key, TValue value, System.Collections.Generic.InsertionBehavior behavior) [0x000dd] in <f98723dd4586469db5213ec59da723ca>:0 
  at System.Collections.Generic.Dictionary`2[TKey,TValue].Add (TKey key, TValue value) [0x00000] in <f98723dd4586469db5213ec59da723ca>:0 
  at Oxide.Plugins.BlueprintManager.OnServerInitialized () [0x00451] in <47ba76c83c0444bda08c9b21d3099864>:0 
  at Oxide.Plugins.BlueprintManager.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x0006a] in <47ba76c83c0444bda08c9b21d3099864>:0 
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <42f9bedc659b4f4786eb778d3cd58968>:0 
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000de] in <112d89ea5d3348c8b949af0ab1a866d2>:0 
  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <112d89ea5d3348c8b949af0ab1a866d2>:0 
Loaded plugin Blueprint Manager v2.1.4 by Whispers88​

FOUND SOLUTION!!!

Deleteing the plugin from the folder and then reuploading it, seems to fix the problem.