Met with this error when trying to build a new character even after starting a new project and importing 2.2:
NullReferenceException: Object reference not set to an instance of an object
Opsive.UltimateCharacterController.Editor.Managers.CharacterManager.DrawNewCharacter () (at Assets/Opsive/UltimateCharacterController/Editor/Managers/CharacterManager.cs:311)
Opsive.UltimateCharacterController.Editor.Managers.CharacterManager.OnGUI () (at Assets/Opsive/UltimateCharacterController/Editor/Managers/CharacterManager.cs:180)
Opsive.UltimateCharacterController.Editor.Managers.MainManagerWindow.OnManagerGUI () (at Assets/Opsive/UltimateCharacterController/Editor/Managers/MainManagerWindow.cs:423)
Opsive.UltimateCharacterController.Editor.Managers.MainManagerWindow.OnGUI () (at Assets/Opsive/UltimateCharacterController/Editor/Managers/MainManagerWindow.cs:326)
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at <437ba245d8404784b9fbab9b439ac908>:0)
Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation.
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at <437ba245d8404784b9fbab9b439ac908>:0)
System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) (at <437ba245d8404784b9fbab9b439ac908>:0)
UnityEditor.HostView.Invoke (System.String methodName, System.Object obj) (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEditor.HostView.Invoke (System.String methodName) (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEditor.HostView.InvokeOnGUI (UnityEngine.Rect onGUIPosition, UnityEngine.Rect viewRect) (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEditor.DockArea.DrawView (UnityEngine.Rect viewRect, UnityEngine.Rect dockAreaRect) (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEditor.DockArea.OldOnGUI () (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEngine.UIElements.IMGUIContainer.DoOnGUI (UnityEngine.Event evt, UnityEngine.Matrix4x4 parentTransform, UnityEngine.Rect clippingRect, System.Boolean isComputingLayout, UnityEngine.Rect layoutSize, System.Action onGUIHandler, System.Boolean canAffectFocus) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.IMGUIContainer.HandleIMGUIEvent (UnityEngine.Event e, UnityEngine.Matrix4x4 worldTransform, UnityEngine.Rect clippingRect, System.Action onGUIHandler, System.Boolean canAffectFocus) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.IMGUIContainer.HandleIMGUIEvent (UnityEngine.Event e, System.Action onGUIHandler, System.Boolean canAffectFocus) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.IMGUIContainer.HandleIMGUIEvent (UnityEngine.Event e, System.Boolean canAffectFocus) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.IMGUIContainer.SendEventToIMGUI (UnityEngine.UIElements.EventBase evt, System.Boolean canAffectFocus) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.IMGUIContainer.HandleEvent (UnityEngine.UIElements.EventBase evt) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.CallbackEventHandler.HandleEventAtTargetPhase (UnityEngine.UIElements.EventBase evt) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.MouseCaptureDispatchingStrategy.DispatchEvent (UnityEngine.UIElements.EventBase evt, UnityEngine.UIElements.IPanel panel) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.EventDispatcher.ApplyDispatchingStrategies (UnityEngine.UIElements.EventBase evt, UnityEngine.UIElements.IPanel panel, System.Boolean imguiEventIsInitiallyUsed) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.EventDispatcher.ProcessEvent (UnityEngine.UIElements.EventBase evt, UnityEngine.UIElements.IPanel panel) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.EventDispatcher.ProcessEventQueue () (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.EventDispatcher.OpenGate () (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.EventDispatcherGate.Dispose () (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.EventDispatcher.ProcessEvent (UnityEngine.UIElements.EventBase evt, UnityEngine.UIElements.IPanel panel) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.EventDispatcher.Dispatch (UnityEngine.UIElements.EventBase evt, UnityEngine.UIElements.IPanel panel, UnityEngine.UIElements.DispatchMode dispatchMode) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.BaseVisualElementPanel.SendEvent (UnityEngine.UIElements.EventBase e, UnityEngine.UIElements.DispatchMode dispatchMode) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.UIElementsUtility.DoDispatch (UnityEngine.UIElements.BaseVisualElementPanel panel) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.UIElements.UIElementsUtility.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr) (at <3736d7cfd1f845a5922f99478cb469e7>:0)
UnityEngine.GUIUtility.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr) (at <817eebdd70f8402280b9cb11fff8b976>:0)