This should do the trick...
Code:
Open: skin1/rectangle_top.tpl
Find: {include file="common_js.tpl"}
Modify: {* include file="common_js.tpl" *}
Add: <script type="text/javascript" src="common_js.js" language="JavaScript 1.2"></script>
Code:
Open: common_js.tpl
Delete: {literal}
Delete: {/literal}
Rename File: common_js.js
I have NOT tested this extensively (just a few clicks around my local install) but I can't see any reason why it wouldn't work...
Also FYI to echo balinor's comment - you can't exactly enter a forum and
demand answers. 99% of this Forum is powered by other users with very little involvement from X-cart staff. Hang in there and usually someone will come through with an answer. If not perhaps no one has an answer just yet...