I have a folder for my custom chewbacca skin, and I put the sounds.cfg and the .skin files in, along with the textures. I have icon images, but how do I get them to work. They are named icon_default, icon_red, and icon_blue. Also, what do I need to get the skin with "bot support" so he can say auto messages and stuff?

When you say, "how can I get them to work," what exactly is the problem you are having?

For bot support, you need to create a bot files that tell the game what powers, abilities, and phrases it has. The easiest way to set these up is to look at ones that come with the game and alter them.