Илья Уткин

foreach ($_GET as $key => $val) {
  $modx->setPlaceholder('GET.'.$key, $val);
}
return '';

[[+GET.param]]

$studios = $modx->getCollection('modResource', $q);

foreach ($studios as $s)
{
	...

   // Во вторую и каждую десятую записи подставляем рекламу из чанка Adv
   if ($n == 2 || ($n-2)%10 == 0){
   	$props['Advertisment'] = $modx->getChunk('Adv', $props);
   }
   $html .= $modx->getChunk($tpl, $props);
}
return($html);

<?php
$bufer = &$modx->resource->_output;
$search = array(
        '/\>[^\S ]+/s',  // strip whitespaces after tags, except space
        '/[^\S ]+\</s',  // strip whitespaces before tags, except space
        '/(\s)+/s'       // shorten multiple whitespace sequences
    );
$replace = array(
        '>',
        '<',
        '\\1'
    );
$buffer = preg_replace($search, $replace, $buffer);

[[pdoResources?
    &tpl=`@INLINE <h3><a href="[[+uri]]">{{+pagetitle:ellipsis=`50`}}</a></h3>
]]