It's normal that the wrapper isn't included, at least right now. In your external page, you could put the opening and closing html of the wrapper around the Portal Island code that you placed on the page.

Hopefully that makes sense. Basically, go into your control panel and then edit the wrapper you want to use. In there you'll see the Opening and Closing HTML. So, in your page, you'd have something like this:

>>OPENING HTML<<

>>ISLAND INCLUDE CODE<<

>>CLOSING HTML<<