It wouldn't let me copy it. :\ I couldn't modify, rename, replace, move, or delete the original bootanimation.zip. Just so I know in the future, what should I do to bypass this?
Also, flashing it via CWM IS specifically outlined at XDA:
1. Download the zip file (1280×720) here.
2. Reboot your phone into recovery.
3. Choose install zip from sd card.
4. Choose zip from sd card.
5. Select the file you downloaded from above.
6. Once it finishes running choose Go Back and then reboot!
Just underneath the Youtube video...