Exception filling window for WorkTab.MainTabWindow_WorkTab: System.NullReferenceException: Object reference not set to an instance of an object
  at WorkTab.PriorityManager.set_ShowPriorities (Boolean value) [0x00000] in <filename unknown>:0
  at WorkTab.MainTabWindow_WorkTab+<>c.<DoToggleButtons>b__31_1 (Boolean val) [0x00000] in <filename unknown>:0
  at WorkTab.InteractionUtilities.ButtonImageToggle (System.Func`1 getter, System.Action`1 setter, Rect canvas, System.String tipOn, UnityEngine.Texture2D texOn, System.String tipOff, UnityEngine.Texture2D texOff) [0x00000] in <filename unknown>:0
  at WorkTab.MainTabWindow_WorkTab.DoToggleButtons (Rect canvas) [0x00000] in <filename unknown>:0
  at WorkTab.MainTabWindow_WorkTab.DoWindowContents (Rect rect) [0x00000] in <filename unknown>:0
  at Verse.Window+<WindowOnGUI>c__AnonStorey0.<>m__0 (Int32 x) [0x00000] in <filename unknown>:0
Verse.Log:Error(String, Boolean)
Verse.<WindowOnGUI>c__AnonStorey0:<>m__0(Int32)
UnityEngine.GUI:CallWindowDelegate(WindowFunction, Int32, Int32, GUISkin, Int32, Single, Single, GUIStyle)