I am unable to download the Swift 2 book The Swift Programming Language, Swift 2 PreRelease version
on my mac, even though i am able to download it on my iPad mini. I keep getting "an unknown error has occurred", & when I try to go to the book description page, i get "that page is temporarily unavailable". iBooks 1.3 (1085.1). And why in hades is that version number in the about box unselectable, unlike every other version # I've ever tried to copy from an about box? OS X 10.11 Beta (15A244d).