Thanks for the links to the blogs. I was wondering how it worked and the "How it works" bit on that page said nothing. Nice that they've explained it. It looks like the blog does answer your questions though:
> The interface which Replay uses for the recording boundary is the API between an executable and the system libraries it is dynamically linked to.
> The interface which Replay uses for the recording boundary is the API between an executable and the system libraries it is dynamically linked to.
I assume the ordered locks use a global order.