Hi Toby,
1) The post you linked to is for Abundance which while similar in a lot of ways, does not have the same social icon set up. So what you'll need to do is copy everything that is in the ul class "social_bookmarks" and put it into the footer.php where you'd like it.
It looks like you've taken this step so far but perhaps not included the php open and closing tags. So in your footer.php where you want to include the social icons add:
<?php
echo '<ul class="social_bookmarks">';
do_action('avia_add_social_icon','header');
if($dribbble = avia_get_option('dribbble')) { $social ++; echo "<li class='dribbble'><a href='http://dribbble.com/".$dribbble."'>".__('Follow us on dribbble', 'avia_framework')."</a></li>"; }
if($twitter = avia_get_option('twitter')) { $social ++; echo "<li class='twitter'><a href='http://twitter.com/".$twitter."'>".__('Follow us on Twitter', 'avia_framework')."</a></li>"; }
if($facebook = avia_get_option('facebook')) { $social ++; echo "<li class='facebook'><a href='".$facebook."'>".__('Join our Facebook Group', 'avia_framework')."</a></li>"; }
if($gplus = avia_get_option('gplus')) { $social ++; echo "<li class='gplus'><a href='".$gplus."'>".__('Join me on Google Plus', 'avia_framework')."</a></li>"; }
if($linkedin = avia_get_option('linkedin')) { $social ++; echo "<li class='linkedin'><a href='".$linkedin."'>".__('Add me on Linkedin', 'avia_framework')."</a></li>"; }
/*
//contact icon
$contact_page_id = avia_get_option('email_page');
if (function_exists('icl_object_id')) $contact_page_id = icl_object_id($contact_page_id, 'page', true); //wpml prepared
if($contact_page_id) { $social ++; echo "<li class='mail'><a href='".get_permalink($contact_page_id)."'>".__('Send us Mail', 'avia_framework')."</a></li>"; }
*/
echo ' <li class="rss"><a href="'.avia_get_option('feedburner',get_bloginfo('rss2_url')).'">RSS</a></li>';
echo '</ul>';
?>
From there, you'll need some additional css fixes depending on where you've added it but they should be fairly simple.
2) I'm not really sure what you mean by setting the size. When you set the number of items to be displayed it automatically sets the size needed. Manual control really isn't possible when adding a portfolio section.
Regards,
Devin