okay, found some software to open the .tar.xz on my Mac (the Unarchiver), so I am gonna try with this one
and.... yes no longer grayed out!
and... yes, there's the jailbreak text!
Thanks!!
Now let's see if I can get the screensaver to show me a book cover instead of the standard screensavers
edit: installed the Screensavers hack
but it won't show the book covers yet
But I'll take that problem to the
right place in this forum...
and another edit: it works now, happy happy joy joy