How to create more columns

it is not so complex to create these files – and with shortcode of columns.php it is easy to have this in a child-theme.
But i realy do not know how to get a “child-theme” avia-builder.js – so that these changings are not lost on update of enfold parent theme.

For your study: webers-testseite.de/6thColumns.zip

Because there has to be changes for admin layout there must be some entries (all included in the zip file)
it does not work to put this css to quick css!

function admin_head_mod() {
echo '<style type="text/css">
.avia_layout_builder .av_one_sixth{width:14%;}
.avia_layout_builder .av_five_sixth {width: 80%;}
</style>';
}
add_action('admin_head', 'admin_head_mod');

you only have to define than – the responsive design.