What I mean by broken is, when you use quit the game, Windows stops responding. I even get the not responding message box pop up stating that "Microsoft Windows is not responding." The whole system freezes, causing me to hold down the power button to the off. Every time I play.
This is true, i have the i5 and there is a quit game bug where when you quit the game buying clicking the cog and choosing quit, it will lock up the os which will eventually get a windows explorer error taking away the taskbar. Only a hard reset will make it better.
The one way to get around the error is to play in windows mode and x out instead of quitting, the OS will not lock up, but your surface may have issues turning off. Everytime i shut down, the next time i turn on the next day, i still get the shutdown screen. So what i do now is x out of hearthstone and then restart my surface and then shut down. THe battle.net forums are filled with this complaint since the patch and still haven't fixed it. Didn't have this issue prior to the patch.
Otherwise, the game works fine as you play.