We've gotten a few reports of crashes when applying the Directional Blur effect (and modifying its properties) in After Effects CS5 on a 12-core Mac. See this post for details and a proposed workaround.
Please use this thread for feedback on this crash and the proposed workaround. Is it working for you? Do you have this crash on a different system?
The "Unexpected data type" error bug and the crash with Directional Blur have been fixed in the After Effects CS5 (10.0.2) update.
Let us know after you've installed the update whether this is working for you.
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