Thank you.
I have put a copy of the page directory (plugins>system>jat3>jat3>base-themes>default>page) into /templates/ja_community_plus/.
The site works fine with that directory placed there.
When I copy the script below into default.php, the website then will not load. (All the other elements you have above is in the file already, so I just copied this script right below the opening <head> tag.
<script async src='https://tag.simpli.fi/sifitag/efb3a550-2c70-0136-474e-067f653fa718'></script>
Here is the full copy of the <head> area that I have for default.php within the/templates/ja_community_plus/page directory.
<head>
<script async src='https://tag.simpli.fi/sifitag/efb3a550-2c70-0136-474e-067f653fa718'></script>
<?php //gen head base on theme info
$this->showBlock ('head');
?>
<?php
$blocks = T3Common::node_children($this->getBlocksXML ('head'), 'block');
foreach ($blocks as $block) :
$this->showBlock ($block);
endforeach;
?>
<?php echo $this->showBlock ('css') ?>
</head>
