PaulS:
I'm using the SdFat library.
Well, it might have been useful to mention that in your post. Or, to include a link.
Yeah, that's totally an oversight on my part. My apologies. I should've said that at the beginning.
But, having said that, I do have a working version after working on both sides of the process all night. I had a small error on the encoding side on the computer which was causing all kinds of odd stuff when I read it back in on the Arduino side. But once that was fixed, then I moved on to doing a continuous read from SD and, while slow, it does work. Not knowing how else to do it, I am doing three consecutive file.read() to get the values for r, g, and b before showing it into the array that the LED library is using.
I suspect once I can figure out how to do the proper reads that things will speed up. It's still nice to see the progress ...