[Plugin: Lightbox Plus] Iframe

I am looking for usage instructions.

I want add to my menu a link to a external website that opens in an iframe. I also want to be able to set the size of the colorbox.

Can someone provide the usage code for this.

I also need to be able to popover a youtube video in the same manner.
Anyone?

http://ww.wp.xz.cn/extend/plugins/lightbox-plus/