How to meet Apple's podcast specs with iWeb

I made a podcast site a few years ago with iTunes using iWeb and Garage Band, but ever since Ape changed the artwork requirements I haven't been able to figure out how to get iWeb to build the pages properly. Does anyone have any insight on this?

Apparently they want to display a 1400 x 1400 piece of artwork at 300 x 300(?). I have Dreanweaver so I can hand code a page, but I'm grey on how it's set up. I've always use the ease of going from GB to iWeb... Has anyone figured this out?...