[Gemma]

I've not tried it with a custom tab. Trying adding both template edits to your custom tab template (where the raw content code should go) so it looks like this:

<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"></script>
<script type="text/javascript" src="twitter/jquery.twitter.js"></script>
 <script src="http://platform.twitter.com/anywhere.js?id=consumer_key&amp;v=1">
  </script>
  <script type="text/javascript">
     twttr.anywhere(function(twitter) {
             twitter.hovercards({ expanded: true });
     });
  </script>
<link rel="stylesheet" type="text/css" href="twitter/twitter.css"/>
<img src="clear.gif" height="10" /><br />
<vb:if condition="$userinfo[fieldXX]">
<div class="blocksubhead subsectionhead userprof_headers userprof_headers_border" >
<h4 id="view-statistics" class="subsectionhead-understate"  style="width:100%">Twitter</h4><br />
</div>
<div class="blockbody subsection userprof_content userprof_content_border">
<h5 class="subblocksubhead subsubsectionhead"><u>Recent Updates:</u></h5>
<div id="twitter_div"> 
<ul id="twitter_update_list"></ul></div>
<script type="text/javascript" src="twitter/blogger.js"></script>
<script text="text/javascript" src="http://twitter.com/statuses/user_timeline/{vb:raw userinfo.fieldXX}.json?callback=twitterCallback2&count=5"></script>
<br><dt class="smallfont">You can follow me on Twitter, my username is <a class="twitter-anywhere-user" href="http://twitter.com/{vb:raw userinfo.fieldXX}">{vb:raw userinfo.fieldXX}</a></dt>
</div></div>
</vb:if>