I have the same problem on my site and ended up just hard coding it to fix the problem. It isn't entering a value for {$style_array['general']}.


In cache_builders/featured_member.php on line 58 I replaced:
Code
$avatar = "{$config['FULL_URL']}/images/{$style_array['general']}/nopicture.gif";
with:
Code
$avatar = "{$config['FULL_URL']}/images/general/default/nopicture.gif";

That obviously isn't the best solution, but it will fix the issue.