I have an issue with my custom skin and it is not loading correctly into the game, I only put the .png into the game, and I am not sure how to fix it, hopefully someone can help me...

PLEASE HELP! How do I add Tracks and Skins, because it only makes one item out of the whole converting process?

I downloaded it and followed all of the steps, and the game works fine, except for the audio. There is none at all, is the anyway to fix this? PLEASE HELP!