Steinberg Hub/Project screen hangs w/ Aero?

I was using Windows Classic desktop mode (win 7 64) for a while, then I read that Aero processing is offloaded to the GPU for most recent video cards (i.e. cards based on WDDM 1.1, which mine is), so I re-enabled an aero theme. However, after a reboot and launching Cubase (7.5.20) it hangs after I select a click on recent project title on the Steinberg Hub screen (mouse busy circle goes on indefinitely; bringing up task manager to close it makes task manager hang as well). If I go back to Windows Classic, it’s fine again. Any ideas what might be going wrong with switching back to Aero?