So I figured out what was happening.
If anyone can show me a way to correct this,
It would be a great help for learning and implementing the scripts in question.

The slimMenu was breaking when I added age verification scripts to:
includes/templates/westminster_new/common/html_header

These scripts specifically:
<link href="includes/templates/westminster_new/css/age-verification.css" rel="stylesheet">
<script src="includes/templates/westminster_new/jscript/jquery-1.11.1.min.js"></script>
<script src="includes/templates/westminster_new/jscript/age-verification.js"></script>
<script src="includes/templates/westminster_new/jscript/jquery.cookie.min.js"></script>


Thanks