Cubase 6.0.4 - Screen Goes Grey/Gray

Hey all,

Just upgraded to Cubase 6 from 5 and loving everything about it, though have noticed a slight little glitch at my side of things:

When working on a very RAM intensive file (instances of EWQLSymphonic Orchestra & Toontrack Drumkit From Hell) for a short time a few bugs were noted:

i. On load up the cursor was dysfunctional, yet my MIDI controller worked fine. Switching to a separate active application and back into Cubase fixed this up.

ii. When dragging multiple audio files (2 or more) simultaneously to different audio tracks the screen would turn a light grey. At first, returning to normal when dropped in place. After further dragging of multiple audio files the screen would not return to normal from its grey state. I have included a picture of this.

Any ideas what might be causing this?

Hardware/Software setup:
MBP 17" running Mac OS X 10.6.8
2.3GHz Intel Core i7
8GB 1333MHz DDR3 RAM
500HB HDD 7200rpm
Cubase 6.0.4
Prism Sound Orpheus Firewire Audio Interface

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