This what the game says about avatars in the manual:
Your Avatar: This is the image that represents you…… You can import your own image into the game.
Attention: You are responsible for the images you choose. This image will be transferred and be visible to other players. Please do not choose images that are shocking or protected by copyrights.
One should always be careful with copyrighted content and shocking stuff. About the latter there is one rule of thumb. Would you want your mother to see your avatar? That said, this tutorial will teach you how to create your own Avatar to personalize your Profile. Other drivers will see this picture next to your name in lists and when you chat.
Key points:
- Authentication. Peer to Peer enabling. Port forwarding.
- Using the game to make an avatar. Why this is not the best option usually.
- Converting a picture to an avatar for better results.
- File sizes and types that avatars have to be within.
- Advanced topics: Transparency, Animated avatars, Polyphonic(emoticons)
- Resources.
Authentication and other important notes:
In order for others to see your avatar on their machine you will need to make sure of a few things. Is your account authenticated? What does that mean? In a nut shell you need purchase Trackmania United You then have a key you are authenticated. . Older keys are no longer accepted. According to Xymph you can authenticate both United and Nations with the player key from your Steam install. It’s in the Nadeo.ini file.
Have you enabled Peer to Peer (P2P) communication in your game? This allows your machine to send a packet with your avatar in it to the other players connected to the same server as you. This can be set in the launcher under the Configure/Advanced/Peer ToPeer tab. Avatars are so small there is no need to make a locator unless you are on dialup and maybe not even then.
In the game there is also a setting under Profile/Advanced menu. Make sure the Show Avatars button is lit to see other people’s avatars.
Port forwarding: Port forwarding is necessary if a router is between your computer and the Internet. Basically it creates a “tunnel” from the web to the local IP address of your computer and the “ports” to which game is listening/using. This enables others to get skins, avatars, locators and other custom content from your machine. How to do this depends on your router and is beyond the scope of this Tutorial. I would suggest doing an internet search for “port forwarding (insert the name and model of your router here)”.
On a side note, port forwarding is necessary if you are behind a router and want to “Create” a server with the game and have others be able to connect. While I’m not absolutely sure that port forwarding is necessary for avatars, anything else that requires a P2P connection does.

