Can you provide more detail as to what you mean by "manual design?"
Hey there.
You have several options:1. You can the AppStylist for ASP.NET, which is part of our NetAdvantage for ASP.NET package. There you can define your own style. You can either use one of the provided as base start point, or define your own from scratch. This approach is suggested and encouraged. This will be easiest to maintain.
2. You can define your own CSS Rules within the IslandStyle. There is CustomRule property, which is exactly what it says: everything you put there as a string, will be rendered as content of style attribute.
3. Every Item (UltreWebMenuItem) exposes CssClass property, which you can set to your custom defined CSS class in your own stylesheet.
You can take a look at this post for little more information: http://forums.infragistics.com/forums/p/17180/63057.aspx
Hope this helps