Get the software working on your computer (laptops work best) being careful to use the correct version of windows (that was the hardest part) and not "bricking" it.
Plug in the connector to your 968 with a round adapter if/as necessary. Run the diagnostics and reset the airbag light. That'll either work or it won't. The last time we used it for this, it worked just fine. If it doesn't work for you, maybe then worry about the seat belts on your 968?