kzarider,
In Mac OS, It is applications that can be launched in either 32 bit or 64 bit mode, not the operating system. (While you can do it by following the Apple knowledgebase info, there is almost no reason to)
It’s Mac OS, not iOS. iOS is the ipad and iphone os.
What you are suggesting is the OP run the Mac operating sytem in 32 bit mode, that would not be such a good idea, since a 32 bit os would only access up to 4gb of ram. (as you said)
The graphic I uploaded shows the Cubase application being set to open in 32 bit mode. Apps that are made to can operate in 32 bit or 64 bit addressing mode on Mac.
So what Chony (who has probably moved on to more interesting things) would want to try is running Cubase as 32 bit or 64 bit.
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Mac OS 10.8.2 Cubase 6.0.7, Cubase 7.0.1, Macbook Pro 2.3ghz 13" 2011, 8gb ram, TC Electronic Konnekt 24d, GPO 4, Zeta Violin, Fatar SL-880 pro, BCF 2000