In the "File space manager", the links to pages point to "approvelist" instead of "filespace".
Quickfix:
In Gallery.template.php find:
if($i == ($page+1))
echo ' [<a href="' . $scripturl . '?action=gallery;sa=approvelist;pg=' . $i . '">' . $i . '</a>]';
else
echo ' <a href="' . $scripturl . '?action=gallery;sa=approvelist;pg=' . $i . '">' . $i . '</a>';
and replace with:
if($i == ($page+1))
echo ' [<a href="' . $scripturl . '?action=gallery;sa=filespace;pg=' . $i . '">' . $i . '</a>]';
else
echo ' <a href="' . $scripturl . '?action=gallery;sa=filespace;pg=' . $i . '">' . $i . '</a>';