OK, scaling.

I have an IFRAME that is effectively using the Embed a Website widget.
The IFRAME ID is iframeEvents.

I add some CSS to present the embedded page at 90%:

<style type="text/css">
#iframeEvents {
zoom: 0.9;
-moz-transform: scale(0.9);
-moz-transform-origin: 0 0;
-o-transform: scale(0.9);
-o-transform-origin: 0 0;
-webkit-transform: scale(0.9);
-webkit-transform-origin: 0 0;
}
</style>

So assuming the page is a known height and width, similar to the Xara design page, then the IFRAME seems to hold the embedded page nicely wrapped by the same styling as the rest of the site.
The IFRAME Placeholder needs to be the actual dimensions of the embedded page so is usually larger on the design page and only "fits" when rendered.

The "better" way would be to use jQuery to abstract all the HTML required to embed directly into a <DIV>, avoiding the IFRAME and unwanted header and footer detail. You would only do this far if the styling of the two pages was radically different.

Acorn