...change the avatar dimensions (size)?

[XiXiDu]

Can I change the maximum size of an avatar and if, where?

Note: The maximum size of your custom image is 50 by 50 pixels or 19.5 KB (whichever is smaller).

Sorry, I can't find it

[Floris]

Hi there, yep, you can change the sizes

Goto the Administrator Control Panel > Usergroups > Usergroup Manager > And edit the usergroup that you want to change this for. (Press the [Go] button).

On the page that loads you will find the "Picture Uploading Permissions" section which will have the settings for the Custom Avatars Upload permissions.

Enjoy!