"Object reference not set to an instance of an object"

I am cutting and pasting from within the .story file--which brings to light another matter since you mentioned it.  I am selecting a slide as an insertion point, and then clicking Insert > Record Screen to create my recording.  Once I have finished recording, I receive the window asking where I want to place the recording.  I pick the correct scene, but it always places it at the end of the scene (I normally create all of my regular slides first, and then create the demos...so there's always slides after my insertion point).   I receive the "object reference" message when I attempt to cut and paste within the scene.