DW doesn't display the div section with CSS. Why?

Question

I was thinking to switch to DW to compose my HTML/CSS pages (I am still using MS Front Page), but when I loaded my HTML page the major <div> section isn't displayed in the Design pane, although it is displayed with the Live view on.
Here's the HTML of the block that is missing:
function(){return A.apply(null,[this].concat($A(arguments)))}
<div id="text_body">
<h1>Description</h1>
Blah-blah-blah
</div>
and CSS file:
function(){return A.apply(null,[this].concat($A(arguments)))}
#text_body
    position: absolute;
    margin-top: -10px;
    padding: 20px;
    width: auto;

Answer 1

Murray, let me reiterate myself. The page in question opens without a problem in a web browser, the issue arises when I
open it in DW for editing, thus posting it somewhere online will look OK to you.
To reproduce what I see, download the zip I posted above and unzip it somewhere on your hard drive (there are only two files in it: html and css). Then open the sample02.htm in DW for editing. After that open it in a web browser of your liking right off your hard drive and you'll see what I'm talking about.
PS. I might be doing something wrong with the DW, since, as I said, I've been using it roughly for a couple of hours. If so, I'd appreciate if someone could point me to what exactly I'm not doing right?