In your Gavick Template go to:
...layouts/blocks/
You will need 2 files:
header.php
footer.php
(not head.php)
Open the header.php file, add your cometchat head code on the first 2 lines:
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js"></script>
<script>jqcc=jQuery.noConflict(true);</script>
Open the footer.php file and again, go to the very bottom and paste the code you get when you install cometchat:
<!-- CometChat Footer Code Start -->
<link type="text/css" rel="stylesheet" media="all" href="cometchat/cometchatcss.php" charset="utf-8" />
<script type="text/javascript" src="cometchat/cometchatjs.php" charset="utf-8"></script>
<!-- CometChat Footer Code End -->
</body>
Replace the 2 php files in your templates layouts/blocks folder and you're good to go!
I did this on Gavicks Quay Template and I just did it on the new PartyFreak Template.
You can see mine at:
http://www.dpwebagency.com/dpstore
HOPE THIS HELPS!!!