Key conflict with script execution order

There is a dictionary conflict with the + button at the bottom of the script execution order screen and a umotion key.  This means I can't add new scripts to the script execution order manifest while I have uMotion installed.

ArgumentException: An item with the same key has already been added. Key: Assets/Plugins/UMotionEditor/Plugins/Application/UMotionApplication.dll.meta

System.Collections.Generic.Dictionary`2[TKey,TValue].TryInsert (TKey key, TValue value, System.Collections.Generic.InsertionBehavior behavior) (at <9577ac7a62ef43179789031239ba8798>:0)

System.Collections.Generic.Dictionary`2[TKey,TValue].Add (TKey key, TValue value) (at <9577ac7a62ef43179789031239ba8798>:0)

UnityEditor.ScriptExecutionOrderInspector.ShowScriptPopup (UnityEngine.Rect r) (at :0)