This isn't an installation from the LiveCD is it? It sounds like a DBus related problem(especially in conjunction with your usb mouting), and I recall DBus problems popping up on Live quite a bit.
No, it's from the Gold ISO, not the Live CD.
If I recall correctly, I did have all the shutdown, log out, reboot options when I first installed, but no longer. I never got all of them on the laptop. I wonder if an update might have affected something.
I'll do more experimenting with the USB flash drives.
--GrannyGeek