Trouble Rendering? It sounds like a tip for a video game, but after effects CS3 and CS4 has secret levels settings. I'm not sure why Adobe is hiding this... but they are. To get around this problem, hold the shift key, go to edit > preferences > memory & cache and you'll be surprised to see a new entry in the drop down menu called 'secret': the most interesting setting is the one that you can clear the memory after a specific amount of rendered images: 'disable layer cache'. put in "3" and see if you are error free.

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