It works flawlessly in Windows 8.1 Pro. I have the AWUS036H model. I was at the boat today and took it home so I could test for you. When you say "crashes" can you be more specific? Do you get a black screen or some kind of error message?

Is it a new PC or have you upgraded your old hardware to 8.1? If the latter did the Alpha work before on this hardware? If not it's possible your USB port isn't capable of powering the Alpha which draws more power than most USB devices, so you might want to try adding a POWERED USB hub into the middle (one that has it's own AC power wall adapter). OR, if the new hardware has a USB 3 port you should use that (some USB 3.0 machines have it on only one port and the others have USB 2.0).

http://alfanetworkinc.blogspot.tw/2012/11/alfa-wifi-usb-adapter-on-windows-8.html