To add the file to your animation:
You will have to edit the desc file the OP has included in the animation package.
add the following to his desc file
s kernkraft400.ogg
Your desc file should look like this:
540 960 11
p 0 0 part0
s kernkraft400.ogg
You can flash his animation through clockwork like he suggested or you can extract the zip from the data/local folder and do it the other way through a root file explorer.
Your system/media folder should already contain an .ogg file of some sort. This is fine, just let it be. Place the new .ogg file in there. The des file the op included, with your additions will point to the new file that you have placed in the system/media folder.
If you are wanting to add this after you have already flashed one of the OP's many fabulous animations, you will have to download it again and edit the desc file and reflash.
Reboot your phone
Profit
Enjoy
<---- .ogg file
All credit goes to the original OP. This animation is his work, he deserves all the credit. I am simply giving you some sound to go with it.