I don't think it's soly a style issue, it works on FF just fine, it's probably an IE7 issue since it's in beta, I've noticed that sometimes pages just don't finish loading in it but I've never noticed it not loading the top part.
Just looked at the source and aside from the fact it's got two doctypes, HTML and Body tags there's nothing wrong with the code.  In fact it's some pretty dang clean code, even using conditional comments for separate IE CSS sheets (which means they'll probably need a new one for IE), their main page is a little wonked in IE 7 too though since there are a few lay out bugs in Beta 3 that shouldn't be there it's hard to tell if it's IE 7s new rendering engine or a bug that's causing it.
[edit] Ya the problem is the center div that's supposed to be inside the main tokyopop "template" is floating way off the screen.
here's the offending code
div#content {
display: block;
float: left;
clear: right;
width: 692px;
margin: -604px 0 0 0;
color: #444;
background-color: #fff;
/*background-image: url('pics/metal_lite_bg.jpg');*/
}
that lovely little -604 on the top margin does it. So ya, they're going to need a new IE7 CSS sheet without that.