just installed avast on Windows 8 Developer preview.
None of the Shields will start and the summary page says "The avast! antivirus program has been stopped, or is in an inconsistent state. Please re-start the program to resume protecting your system."
When I try to register for a free license it fails and I get the error "The AAVM subsystem detected a RPC error"
I'm not worried about this at all since its not even a beta product of Windows 8. Just reporting my findings for you guys' information.