Workaround for issue with black screen in Windows 8 with guest tools installed.
Shut down virtual machine.
Open [Virtual Machine Configuration > Hardware > Boot Order] and locate [Boot flags].
In [Boot flags] write:
Run virtual machine. Install Parallels Tools (if not yet).
Known issues with that workaround: Coherence, Dynamic Resolution, Smart Mouse (Sliding Mouse) will not work.
However, Smart Mouse (Sliding Mouse) can be enabled manually.
Open [Virtual Machine Configuration > Options > Advanced] and set [Smart Mouse] to [On].
This will allow Smart Mouse to work in Windows 8 even when described workaround applied.