I suppose the items you want to load are located in the extras CD, their preview shows a CD in the bottom right corner? meéans you need to download your Xtras CD from your e-on account page.

If it shows the Cornucopia3d logo, then it means it's an item you can buy from the Cornucopia3D website, but you can do so without leaving Vue (provided you have an account, which is not the case yet, apparently). So take a look at the icon in the bottom right corner of the preview of the item, if a disc, then it's on the extras CD, if a Cornucopia, it's an item you have to buy from C3D.