Sorry I didn't get a chance to work on this yesterday! Work etc.
I'll check it out tonight to give you an example, but the punchline is.
On Start of Layout:
Replace Cursor with Sprite -> Sprite that conforms to the guide above.
(28 x 28 PNG) with no effects.
Does not work. Simply just doesn't happen when exported as an NW JS app, or in the preview.
On the other hand, Set Cursor Style -> Whatever, works fine.
I'll get more detail when I'm back at home - thanks for patience.