Website creation help needed

Hi,
I'm trying to create a website, mainly to host my photos, but also for some other things.
I haven't even got so far as to actually add content yet, and I'm already stuck.
Man, am I dreading the day when I'll try to add my flash gallery.:p

Anyway, my problems are both related to layout issues, and probably both also to the file "styles.css" (available inside the .zip with the website files, link further down). I've tried to explain the problems as good as possible in the image below:

HTTP response: 404 | MIME changed to 'text/html' | Byte size: ZERO

With regards to the image-

Rename the div that the header image resides in, in the HTML for each page:

<div class="Visual"> </div>

<div class="Home_Visual"> </div>

<div class="Gallery_Visual"​> </div>

<div class="New_Visual"> </div>

etc...

#HEADER .Visual{ height:130px; background-image: url(bg_visual.jpg);  background-repeat: no-repeat;  background-color: #4492C8;  border-top: 3px solid Black;   }

#HEADER .Home-Visual{ height:130px; background-image: url(**NEW_IMAGE_FILENA​ME_HERE**);  background-repeat: no-repeat;  background-color: #4492C8;  border-top: 3px solid Black;   }