document.write statement, the simple, non-blocking solution detailed below may work for you.
var params =
id: "[Your ID value]",
d: "[Your D value]",
wid: "[Your WID value]",
cb: (new Date()).getTime()
for(var key in params) qs.push(key+'='+encodeURIComponent(params[key]));
var p = 'https:' == document.location.protocol ? 'https' : 'http';
s.src = p + "://api.content.ad/Scripts/widget2.aspx?" + qs.join('&');
d.getElementById("contentad[Your WID value]").appendChild(s);
In the body of the page, place the following code where you would like the widget to appear:
<div id="contentad[Your WID value]"></div><!-- Load Widget Here --></div>
If you are unable to add HTML to the page:
Skip the second step, and change the line
document.getElementById("contentad[Your WID value]").appendChild(s); so that the value of getElementById is the ID of an element currently on the page inside of which you would like the widget to appear.