I apologize if this sounds old and redundant, and possibly already solved. But I've encountered this same problem with my Macbook Pro. I purchased the CS3 Master and I've just gotten around now to use the Brainstorm function, which gives me the same error. Has this been fixed?
Have you tried re-creating preferences?
Just rename or trash the "After Effects 8.0 prefs" file in Library/Preferences/Adobe/After Effects/8.0.
Of course, also make sure you're running the latest update for CS3 (AE 8.02).
Awesome! That did the trick! Thanks!