I've installed CustoMenu fot create rollover menu's in the topmenu horizontal - without text, only images. (joomla 1.5.7)

Where do I have to apply CustoMenu ? Do I have to create classes in the template CSS ? Of is there a CSS for CustoMenu separately ?

Are there examples to get started ?

My CSS template - details on pillmenu, as it is now. Can I use this to start ?

#pillmenu {
white-space: nowrap;
float: none;
margin: 0;
height: 74px;
}

#pillmenu ul {
margin: 0;
padding: 0 0 0 0px;
list-style: none;
}

#pillmenu li {
float: left;
margin: 0;
padding: 0;
height: 57px;
}

#pillmenu li a {
font-family:Tahoma;
font-size: 11px;
float: left;
display: block;
line-height: 57px;
padding: 0 1px 0 0px;
color: #000000;
text-decoration: none;
font-weight: bold;
}

#pillmenu li a:hover {
color: #C72319;
}

#pillmenu li.item2 a {
width: 115px;
height:74px;
background: url(../images/stories/nieuws.jpg) 0 0 no-repeat;
}


Should I add classes like this ?

#pillmenu li.item2 a {
width: 115px;
height:74px;
background: url(../images/stories/nieuws.jpg) 0 0 no-repeat;
}

#pillmenu li.item2 a:hover, #topmenu li#current.item2 a {
background: url(../images/stories/nieuws_over.jpg) 0 0 no-repeat;
}

#pillmenu li.item3 a {
width: 115px;
height:74px;
background: url(../images/stories/interieur.jpg) 0 0 no-repeat;
}

#pillmenu li.item3 a:hover, #topmenu li#current.item3 a {
background: url(../images/stories/interieur_over.jpg) 0 0 no-repeat;
}

There is a CSS that comes with CustoMenu.
If your stylename is default, then the default.css will be used.
If you change it to something like mystyle, the mystyle.css will be used.
The css files are located in /modules/mod_customenu/css

You can also just put all your menu styles in your template css. But the structure and class names are different to the pillmenu.

ah, but I cannot see this default css in the back-end. Do I have to open it with an ftp programme and then copy and paste into de template css ?

Yep. I have just released a completely new version of CustoMenu btw.