I know you've been playing with the Site Builder, so if your on one of those pages, put the code into the CODE tab of the widget, not the editor.
eg:
* add a widget
* click on the "Widget Settings" button to show the editor
* look in the top left corner of that popup and you will see EDITOR | CODE. Click on the CODE button to change the editor to the code view.
The EDITOR and the CODE views are
completely separate its one or the other that is showing. If your wanting to put in some script, then use the CODE.
eg, to put the twitter widget code in there, use this code:
<a class="twitter-timeline" href="https://twitter.com/jamroomdev" data-widget-id="456325856210599936">Tweets by @jamroomdev</a>
<script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+"://platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");</script>
That example code will put the twitter widget for @jamroomdev on your page.
One important thing to note though that could screw things up, is if the code is compressed.
Smarty code is enclosed in brackets {$something} and javascript also uses {}. Smarty will ignore javascripts brackets as long as there is a space between the { and the first letter.
So if your code looks like this:
.....mentById(id)){js=d.createE.......
you need to add a space between the { and the next character.
Needs to become
.....mentById(id)){ js=d.createE.......
So a working version of that twitter code above would be:
<a class="twitter-timeline" href="https://twitter.com/jamroomdev" data-widget-id="456325856210599936">Tweets by @jamroomdev</a>
<script>!function(d,s,id){ var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){ js=d.createElement(s);js.id=id;js.src=p+"://platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");</script>