I turn off my computer by Classic Shell start-up menu shut-down button on Windows 8 x64. And I found there is a bug about the shut-down process:
It just different than the built-in Top-right conner --> setting --> power ---> Shut down. It won't install system update nor when I changed something in Registry, the modified keys won't take effect the next time I turn on the machine...
The later problem haunted me a few day when I try to turn of the Low Disk Space Warning notification.
Windows 8 x64
Classics Shell 3.6.2
Installing updates is not supported. There is not API for that so only the OS can do it.
The registry issue maybe related to hybrid shutdown. This is the default on Windows 8. Try holding down Shift while shutting down to get a full shutdown.
Also have the shutdown issue.
Windows 8 Pro x64
Classics Shell 3.6.6
Have confirmed that this is only an issue when activating shutdown or restart via Classics Shell, and shutdown otherwise operates normally when activated via the other normal Windows 8 methods.
Holding down shift when shutting down via Classic Shell does work as a workaround but the reason for using Classic Shell was so that users weren't required to learn anything new over Windows 7, so it is not really a workaround.