It should show up right away, so you must be stupid
heh, just kidding. Here is how to add a custom avatar.
1. Find the avatar you want and make sure it is no bigger than 90x90 and 18,000 Bytes in size.
2. Click on "User CP" then "Edit Options".
3. Scroll down to where it says "Other Options" and click on the "Change Avatar" button near the bottom right.
4. Put in the URL to your avatar or else upload it, then click ok.
Assuming you did it all right, it should show up. If for some reason you are still having problems with it, just post a message here and attach the avatar and i'll do it for you.
- SkuZZy