Ok, for the latest post from a specific thread, I believe I found the way to do so (untested).
First, make a backup of your member.php file.
Then, find this block :
$user_icq = (isset($user_row['user_icq'])) ? $user_row['user_icq'] : REPLACE_EMPTY;
if (!empty($user_icq) && $user_icq != REPLACE_EMPTY) {
$user_icq_button = "<a href=\"http://wwp.icq.com/scripts/search.dll?to=".$user_icq."\" target=\"_blank\"><img src=\"http://web.icq.com/whitepages/online?icq=".$user_icq."&img=5\" width=\"18\" height=\"18\" border=\"0\" alt=\"".$user_icq."\" /></a>";
}
else {
$user_icq_button = REPLACE_EMPTY;
}
add below :
$boardgories = "
SELECT catid, catname
FROM ".BOARD_CAT_TABLE."
";
$result = $site_db->query($boardgories);
$dboard_cat_row = $site_db->fetch_array($boardgories);
$board_catid = $dboard_cat_row['catid'];
$dreamboard_selection = "
SELECT board_id, board_catid, board_name, board_desc, board_posts, board_topics, board_lastpost_id, board_lastpost_user, board_lastpost_date, board_lastpost_page, board_moderator, board_moderator_id, auth_view
FROM ".BOARD_TABLE."
WHERE board_catid = '".$board_catid."'
LIMIT 1
";
$result = $site_db->query($dreamboard_selection);
$dboard_row = $site_db->fetch_array($result);
$board_id = $dboard_row['board_id'];
$board_catid = $dboard_row['board_catid'];
$board_name = $dboard_row['board_name'];
$board_desc = $dboard_row['board_desc'];
$board_topics = $dboard_row['board_topics'];
$board_posts = $dboard_row['board_posts'];
$board_lastpost_id = $dboard_row['board_lastpost_id'];
$board_lastpost_user = $dboard_row['board_lastpost_user'];
$board_lastpost_date = $dboard_row['board_lastpost_date'];
$board_lastpost_page = $dboard_row['board_lastpost_page'];
$board_moderator = $dboard_row['board_moderator'];
$board_moderator_id = $dboard_row['board_moderator_id'];
$auth_view = $dboard_row['auth_view'];
$newlastpost = "<img src=\"".TEMPLATE_PATH."/board_images/new_last_post.gif\" border=\"0\" alt=\"".$lang['button_lastpost']."\">";
Then, find :
"user_icq_status" => (isset($user_row['user_icq'])) ? get_icq_status($user_row['user_icq']) : REPLACE_EMPTY,
add right below :
"lang_dboard_lastpost_topic" => $lang['dboard_user_lastposted'],
"dboard_lastpost_topic" => "<a href=\"".$site_sess->url(ROOT_PATH."showthread.php?bid=".$board_id."&threadid=".$board_lastpost_id."&page=".$board_lastpost_page)."\">".$newlastpost."</a>",
Then, in your lang/english/main.php file,
add before the : "?>" tag :
$lang['dboard_user_lastposted'] = "Last post from user:";
Then, on your member_profile.html file,
you should now be able to use these two tags :
{lang_dboard_lastpost_topic}
{dboard_lastpost_topic}
Note: Remember that this is untested.

Let me know how it goes.