Can you copy and paste the full error that you are receiving? I need to see the line number causing the problem.
IndexOutOfRangeException: Index was outside the bounds of the array.
Opsive.UltimateCharacterController.Editor.Inspectors.Camera.CameraControllerInspector.OnViewTypeStateListDraw (UnityEngine.Rect rect, System.Int32 index, System.Boolean isActive, System.Boolean isFocused) (at Assets/Opsive/UltimateCharacterController/Editor/Inspectors/Camera/CameraControllerInspector.cs:388)
UnityEditorInternal.ReorderableList.DoListElements (UnityEngine.Rect listRect, UnityEngine.Rect visibleRect) (at <3164af17d5d94ab0bb0c3556307c8722>:0)
UnityEditorInternal.ReorderableList.DoList (UnityEngine.Rect rect, UnityEngine.Rect visibleRect) (at <3164af17d5d94ab0bb0c3556307c8722>:0)
UnityEditorInternal.ReorderableList.DoList (UnityEngine.Rect rect) (at <3164af17d5d94ab0bb0c3556307c8722>:0)
Opsive.Shared.Editor.Inspectors.StateSystem.StateInspector.DrawStates (UnityEditorInternal.ReorderableList reorderableList, UnityEditor.SerializedObject serializedObject, UnityEditor.SerializedProperty states, System.String selectedIndexKey, UnityEditorInternal.ReorderableList+ElementCallbackDelegate drawCallback, UnityEditorInternal.ReorderableList+AddCallbackDelegate addCallback, UnityEditorInternal.ReorderableList+ReorderCallbackDelegate reorderCallback, UnityEditorInternal.ReorderableList+RemoveCallbackDelegate removeCallback) (at Assets/Opsive/Shared/Editor/Inspectors/StateSystem/StateInspector.cs:84)
Opsive.UltimateCharacterController.Editor.Inspectors.Camera.CameraControllerInspector.DrawSelectedViewType (System.Int32 index) (at Assets/Opsive/UltimateCharacterController/Editor/Inspectors/Camera/CameraControllerInspector.cs:364)
Opsive.UltimateCharacterController.Editor.Inspectors.Utility.ReorderableListSerializationHelper.DrawReorderableList (UnityEditorInternal.ReorderableList& reorderableList,
Opsive.Shared.Editor.Inspectors.InspectorBase inspector, System.Array drawnObject, System.String serializedData, UnityEditorInternal.ReorderableList+HeaderCallbackDelegate drawHeaderCallback, UnityEditorInternal.ReorderableList+ElementCallbackDelegate drawElementCallback, UnityEditorInternal.ReorderableList+ReorderCallbackDelegate reorderCallback, UnityEditorInternal.ReorderableList+AddCallbackDelegate addCallback, UnityEditorInternal.ReorderableList+RemoveCallbackDelegate removeCallback, UnityEditorInternal.ReorderableList+SelectCallbackDelegate selectCallback, System.Action`1[T] drawSelectedElementCallback, System.String key, System.Boolean requireOne, System.Boolean
indentList) (at Assets/Opsive/UltimateCharacterController/Editor/Inspectors/Utility/ReorderableListSerializationHelper.cs:91)
Opsive.UltimateCharacterController.Editor.Inspectors.Camera.CameraControllerInspector.<GetDrawCallback>b__13_0 () (at Assets/Opsive/UltimateCharacterController/Editor/Inspectors/Camera/CameraControllerInspector.cs:150)
Opsive.Shared.Editor.Inspectors.StateSystem.StateBehaviorInspector.OnInspectorGUI () (at Assets/Opsive/Shared/Editor/Inspectors/StateSystem/StateBehaviorInspector.cs:92)
UnityEditor.UIElements.InspectorElement+<>c__DisplayClass59_0.<CreateIMGUIInspectorFromEditor>b__0 () (at <b0c6c7bf97154d4994cbc2e652831a43>:0)
UnityEngine.GUIUtility: ProcessEvent(Int32, IntPtr, Boolean&)