The Nestabilities will work in the Original Sizzix machine. That is what I have been using. I have only cut with them so far, I have not attempted the embossing.
You need the Sizzix
Adapter and the Sizzix
Converter to make them work. Then you just put your cardstock on the cutting pad, the nestability ridge side down, final the adapter. The die always get stuck in the cutting pad, but it is pretty easy to get it unstuck.
I love the Nestabilities!