I installed Q&A Lite and I’m pretty happy with it for now.
Sadly visitors always get redirected to the Homepage when they click my menu link for “Q&A” (which refers to intranet.ammarkt.ch/questions). When I’m logged in, everything works just fine. Besides I don’t see a visitor user-type in settings. I only see “Spectator” and “Keymaster” (whatever that might be).