I just purchased and imported NC:Behavior. I attached the Behavior Tree Owner and Blackboard scripts to an object and opened a new behavior in the editor. When I right click in the editor or to add a blackboard variable nothing happens and I get the error message below. I tried deleting the folder and importing it again and the same thing is happening. How can I fix this?

ReflectionTypeLoadException: The classes in the module cannot be loaded.
System.Reflection.Assembly.GetTypes () (at /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/Assembly.cs:371)
NodeCanvas.EditorUtils.GetAssemblyTypes (System.Type baseType) (at Assets/NodeCanvas/Core/Other/EditorUtils.cs:764)
NodeCanvas.EditorUtils.GetAllScriptsOfTypeCategorized (System.Type baseType) (at Assets/NodeCanvas/Core/Other/EditorUtils.cs:724)
NodeCanvas.EditorUtils.ShowTypeSelectionMenu (System.Type baseType, System.Action`1 callback) (at Assets/NodeCanvas/Core/Other/EditorUtils.cs:698)
NodeCanvas.Graph.DoGraphControls () (at Assets/NodeCanvas/Core/Graph/Graph.cs:926)
NodeCanvas.Graph.ShowGraphControls () (at Assets/NodeCanvas/Core/Graph/Graph.cs:819)
NodeCanvasEditor.GraphEditor.OnGUI () (at Assets/NodeCanvas/Core/Editor/GraphEditor.cs:168)
System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:222)