Oi ciao a tutti!
Io sono alle prime armi, sto montando un sito personale.
Ho implementato un menù con image replace che funziona correttamente su eXPL 6 e che in testing funzionava anche su Mozilla Firefox 2, ora che ho terminato il menù della home e quello delle altre pagine, il tutto non funziona più su Firefox, appunto.

Mi sono accorto studiando in giro di aver commesso errori nell'HTML, usando tabelle invece dei <div> e non avendo pensato a porre un elemento contenitore.
Possono essere queste le cause del mal funzionamento?

il mio sito: bi-unic.com

il mio css:

/* CSS Document */

body {
background-color: #000000;
font-family: Arial, Helvetica, sans-serif;
color: #FFFFFF;
font-size: 12px;
margin:0px;
}

/* Measurements for the nav image replacement MenuHome:
The distance from the top to the...
initial state = 0px
rollover state = 542px
selected state = 542px
The distance from the far-left to the...
Quim Somos button = 0px
ShowRoom button = 106px
Coleçoes button = 234px
ConactUs button = 346px
News button = 486px
The width of the...
Quem Somos button = 106px
ShowRoom button = 128px
Coleçoes button = 112px
ConactUs button = 140px
News button = 116px
*/

ul#nav { background:url(img/MenuHome.gif);
}

ul#nav li {
float:left;
list-style-type:none;
}

ul#nav li a { height:542px;
display:block;
position:inherit;
top:0px;
padding:20px;
margin-bottom:150px;
text-indent:-9999px;
overflow:hidden;
outline:none;
}

li#navQuemSomos a, li#navShowRoom a, li#navColecoes a, li#navContactUs a, li#navNews a { background:url(img/MenuHome.gif);
}

li#navQuemSomos a { background-position:0 0; width:106px; left:0
}

li#navQuemSomos a:hover { background-position:0 -542px ! important;
}

li#navShowRoom a { background-position:-106px 0; width:128px; left:106px
}

li#navShowRoom a:hover { background-position:-106px -542px
}

li#navColecoes a { background-position:-234px 0; width:112px; left:234px
}

li#navColecoes a:hover { background-position:-234px -542px
}

li#navContactUs a { background-position:-346px 0; width:140px; left:346px
}

li#navContactUs a:hover { background-position:-346px -542px
}

li#navNews a { background-position:-486px 0; width:116px; left:486px }

li#navNews a:hover { background-position:-486px -542px
}


.logoSmall {
position:relative;
top:-315px;
left:2px;
}

.footer {
font-family:Arial, Helvetica, sans-serif;
color:#FF0000;
font-size:12px;
margin:0px;
position:absolute;
left:38%;
outline:none;
}

.footer a {
color:#FFFFFF;
outline:none;
}

.footerStrips {
background-image:url(img/PatternFooter.gif);
background-repeat:repeat-x;
position:relative;
top:-60;
text-indent:-9999px;
}

/* Measurements for the nav image replacement NAV2:
The distance from the top to the...
initial state = 0px
rollover state = 45px
selected state = 45px
The distance from the far-left to the...
Home button = 0px
Quim Somos button = 97px
ShowRoom button = 207px
Coleçoes button = 317px
ConactUs button = 428px
News button = 537px
The width of the...
Home button = 97px
Quem Somos button = 110px
ShowRoom button = 110px
Coleçoes button = 111px
ConactUs button = 109px
News button = 113px
*/

ul#nav2 { background:url(img/MenuNav2.gif);
}

ul#nav2 li {
float:left;
list-style-type:none;
}

ul#nav2 li a { height:45px;
display:block;
position:relative;
top:0;
left:230px;
margin-top:10px;
text-indent:-9999px;
overflow:hidden;
outline:none;
}

li#nav2Home a, li#nav2QuemSomos a, li#nav2ShowRoom a, li#nav2Colecoes a, li#nav2ContactUs a, li#nav2News a { background:url(img/MenuNav2.gif);
}

li#nav2Home a { background-position:0 0; width:97px; left:0
}

li#nav2Home a:hover { background-position:0 -45px ! important;
}


li#nav2QuemSomos a { background-position:-97px 0; width:110px; left:97px
}

li#nav2QuemSomos a:hover { background-position:-97px -45px ! important;
}

body#pageQuemSomos li#nav2QuemSomos a { background-position:-97px -45px;
}

li#nav2ShowRoom a { background-position:-207px 0; width:110px; left:207px;
}

li#nav2ShowRoom a:hover { background-position:-207px -45px ! important;
}

body#pageShowRoom li#nav2ShowRoom a { background-position:-207px -45px
}


li#nav2Colecoes a { background-position:-317px 0; width:111px; left:317px;
}

li#nav2Colecoes a:hover { background-position:-317px -45px ! important;
}

body#pageColecoes li#nav2Colecoes a { background-position:-317px -45px;
}

li#nav2ContactUs a { background-position:-428px 0; width:109px; left:428px;
}

li#nav2ContactUs a:hover { background-position:-428px -45px ! important;
}

body#pageContactUs li#nav2ContactUs a { background-position:-428px -45px;
}

li#nav2News a { background-position:-537px 0; width:113px; left:537px }

li#nav2News a:hover { background-position:-537px -45px ! important;
}

body#pageNews li#nav2News a { background-position:-537px -45px;
}

.cab {
font-family:Arial, Helvetica, sans-serif;
color:#FF0000;
font-size:16px;
font-weight:200;
position:relative;
margin-top:100px;
margin-bottom:30px;
}

.formCnc {
font-family:Arial, Helvetica, sans-serif;
color:#FF0000;
font-size:12px;
position:relative;
margin:50px;
}

ul.contact p {
font-family:Arial, Helvetica, sans-serif;
color:#FF0000;
font-size:12px;
position:relative;
margin-top:15px;
margin-bottom:0px;
}


Grazie!