why everytime shutting down windows 8 an blank black screen appears and only way to shutdown is doing force close/stop of the virtual machine?
Windows 8 Dev Preview, right? Well, as far as I can tell the Windows is completely shut by that time, Parallels just doesn't get aware of that. Out of curiosity. Have you tried installing Parallels Tools? I tried it but the screen gets black after login, some problem with the Video Driver and the new Desktop model, I think.