Aún no sale una version del advance quick reply para 1.6, pero la verdad y probando, eso solo cosa de modificar la plantilla de la respuesta rápida.
te dejo la planyilla que le tengo puesta yo.
showthread_quickreply:
<form method="post" action="newreply.php?tid={$tid}&processed=1" name="quick_reply_form" id="quick_reply_form">
	<input type="hidden" name="my_post_key" value="{$mybb->post_code}" />
	<input type="hidden" name="subject" value="RE: {$thread['subject']}" />
	<input type="hidden" name="action" value="do_newreply" />
	<input type="hidden" name="posthash" value="{$posthash}" id="posthash" />
	<input type="hidden" name="quoted_ids" value="" id="quoted_ids" />
	<input type="hidden" name="lastpid" id="lastpid" value="{$last_pid}" />
	<input type="hidden" name="from_page" value="{$page}" />
	<input type="hidden" name="tid" value="{$tid}" />
	<input type="hidden" name="method" value="quickreply" />
	<table border="0" cellspacing="{$theme['borderwidth']}" cellpadding="{$theme['tablespace']}" class="tborder">
		<thead>
			<tr>
				<td class="thead" colspan="2">
					<div class="expcolimage"><img src="{$theme['imgdir']}/collapse{$collapsedimg['quickreply']}.gif" id="quickreply_img" class="expander" alt="[-]" title="[-]" /></div>
					<div><strong>{$lang->quick_reply}</strong></div>
				</td>
			</tr>
		</thead>
		<tbody style="{$collapsed['quickreply_e']}" id="quickreply_e">
			<tr>
				<td class="trow1" valign="top" width="23%">
<div>
					{$clickablesmilies}
</div>
{$closeoption}
				</td>
				<td class="trow1" valign="top">
<strong>{$lang->message}</strong><br />
<span class="smalltext">{$lang->message_note}<br /></span>
					<div style="width: 100%">
						<textarea style="width: 95%; padding: 0px; margin: 0;" rows="18" cols="65" name="message" id="message" tabindex="1"></textarea>
{$codebuttons}
					</div>
					<div class="editor_control_bar" style="width: 95%; padding: 4px; margin-top: 3px; display: none;" id="quickreply_multiquote">
						<span class="smalltext">
							{$lang->quickreply_multiquote_selected} <a href="./newreply.php?tid={$tid}&load_all_quotes=1" onclick="return Thread.loadMultiQuoted();">{$lang->quickreply_multiquote_now}</a> {$lang->or} <a href="javascript:Thread.clearMultiQuoted();">{$lang->quickreply_multiquote_deselect}</a>.
						</span>
					</div>
<span class="smalltext">
<label>
<input type="checkbox" class="checkbox" name="postoptions[signature]" value="1" {$postoptionschecked['signature']} /> 
<strong>{$lang->signature}</strong>
</label>
<label>
<input type="checkbox" class="checkbox" name="postoptions[disablesmilies]" value="1" /> 
<strong>{$lang->disable_smilies}</strong>
</label>
</span>
				</td>
			</tr>
			{$captcha}
			<tr>
				<td colspan="2" align="center" class="tfoot"><input type="submit" class="button" value="{$lang->post_reply}" tabindex="2" accesskey="s" id="quick_reply_submit" /> <input type="submit" class="button" name="previewpost" value="{$lang->preview_post}" tabindex="3" /></td>
			</tr>
		</tbody>
	</table>
</form>
Puedes copiar y pegarlo en el tuyo.
ahi si le quieres hacer algún edit de posicionamiento nada más editas el hatml.
Así es como se ve en mi foro:
[Imagen: pantallazokd.png]