Hello,
You can use HTML attributes, CSS styles or a MS Word custom table style.
For example, the following script removes the border and set a border-collapse:
<?php
require_once 'classes/CreateDocx.php';
$docx = new CreateDocx();
$html = '
<style>
table, th, td { border: 0; }
table {border-collapse: collapse;}
</style>
<table>
<tbody>
<tr width="600">
<td style="background-color: yellow">1_1</td>
<td rowspan="3" colspan="2">1_2</td>
</tr>
<tr width="600">
<td>Some random text.</td>
</tr>
<tr width="600">
<td>
<ul>
<li>One</li>
<li>Two <b>and a half</b></li>
</ul>
</td>
</tr>
<tr width="600">
<td>3_2</td>
<td>3_3</td>
<td>3_3</td>
</tr>
</tbody>
</table>';
$docx->embedHTML($html);
$docx->createDocx('output');
If you open the DOCX output with MS Word 2003 or newer or LibreOffice 5 or newer, you can check there's no border and the table is 'collapse'.
A very similar sample is included in the package (examples/Core/embedHTML folder).
Regards.