A good place to start: the video footage you used. Can you tell us about it? Media container & codec?
The video sent to me by the client is 1920x1080, compressed with h264, and a .mp4 container. I realize now that is probably what's taxing the computer unnecessarily. I would have preferred something less compressed as possible, especially with the amount of effects applied to the sequence. I am basically doing this as a favor for a friend and am not particularly advanced in After Effects, I only use it from time to time. If I wasn't basically finished with the project I would just start over with a new version of the video file I use in the comp, but I don't have the time to re-do everything
Earlier today I was able to render a proxy version of the composition without any errors, so I assume the errors are due to that video being too compressed and the comp has trouble applying those color FX to it, so it crashes? I never color correct anything that is h264 so I should have figured not use an h264 file in AE especially with the amount of effects applied to it.
Live and learn I suppose!
Thanks for the response Dave!
You can still have success by transcoding the h.264 footage to something less processor-intensive: JPEG 2000, Photo JPEG, and Animation come to mind. Then use the Replace Footage command to substitute the new footage for the older, problem footage. If you transcode all of the footage, preserving the original frame rate, interlacing, etc. the replacement will be seamless.