Exception filling window for RimWorld.Dialog_FormCaravan: System.NullReferenceException: Object reference not set to an instance of an object
at WhatTheHack.Utilities.CalcDaysOfFuel (System.Collections.Generic.List`1<RimWorld.TransferableOneWay>) <IL 0x0003e, 0x0010b>
at WhatTheHack.Harmony.Dialog_FormCaravan_CountToTransferChanged.Postfix (RimWorld.Dialog_FormCaravan) <IL 0x00007, 0x00026>
at (wrapper dynamic-method) RimWorld.Dialog_FormCaravan.CountToTransferChanged_Patch1 (object) <IL 0x0002d, 0x00050>
at RimWorld.Dialog_FormCaravan.DoWindowContents (UnityEngine.Rect) [0x00268] in C:\Dev\RimWorld\Assets\Scripts\RimWorld\UI\Dialogs\Dialog_FormCaravan.cs:453
at Verse.Window/<WindowOnGUI>c__AnonStorey0.<>m__0 (int) [0x00223] in C:\Dev\RimWorld\Assets\Scripts\Verse\UI\Windows\Window.cs:202

Verse.Log:Error(String, Boolean) (at C:\Dev\RimWorld\Assets\Scripts\Verse\Utility\Debug\Log\Log.cs:78)
Verse.<WindowOnGUI>c__AnonStorey0:<>m__0(Int32) (at C:\Dev\RimWorld\Assets\Scripts\Verse\UI\Windows\Window.cs:206)
UnityEngine.GUI:CallWindowDelegate(WindowFunction, Int32, Int32, GUISkin, Int32, Single, Single, GUIStyle) (at C:\buildslave\unity\build\Runtime\IMGUI\Managed\GUI.cs:1817)