Et voilà, my first big issue with Windows 8: unable to logon after installing Ricoh Multi Card Reader drivers on Lenovo T 520.
The drivers have installed successfully and after the reboot, the logon screen was plain – no more way to enter credentials 
With this important issue, I also discovered that return to ‘Last known good configuration’ is non existent on this beta version
Ok, I know this is beta but I never had such important issue with previous Windows beta (since Windows 2000 to Windows 7).
UPDATE
Hotkey Features Integration for Windows 7 do the same thing.