Lotsa people having problems that are most likely related…
I get a similar message to yours, if I try to restart cubase after it has crashed:
0xCB DRIVER_LEFT_LOCKED_PAGES_IN_PROCESS in module KS.SYS
Basically, if Cubase 6 ends unexpectedly, I need to a do a reboot otherwise I have a got a BSOD coming my way…
(Yes, I am on WinXP, but clearly this is not a WinXP-only issue)