[@livibetter Member 17 years, 2 months ago]

Replace line 194 in bb-avatar-upload.php

$felidenticon = $identicon->identicon_build( $user->user_login, '', false, '', false );

with

$felidenticon = $identicon->identicon_build( (($user->display_name) ? $user->display_name : $user->user_login), '', false, '', false );

PS. Just a quick guessing solution and I haven’t used this plugin.