By the way, this is how I tackle the issue with non-Steam avatars not showing up using the method outlined previously in this thread. I'm sure the code isn't proper and I'm no programmer but this works for me.
PHP Code:
<vb:if condition="$post['steam_code']"><a href="http://steamcommunity.com/profiles/{vb:raw post.steamid}" target="_blank" title="{vb:rawphrase {vb:raw post['onlinestatusphrase']}, {vb:raw post.username}}"><img src="{vb:raw post.steamavatarmedium}" /></a>
<vb:else /><a class="postuseravatar" href="{vb:link member, {vb:raw post}}" title="{vb:rawphrase {vb:raw post['onlinestatusphrase']}, {vb:raw post.username}}"><img src="{vb:raw post.avatarurl}" /></a>
</vb:if>