I just had a quick glance. It appears you still haven't fixed this.
Did you experiment with the css? I appears the menu container isn't wide enough, maybe you can try to set a width: 100%; on either or both of these containers
<div class="AspNet-Menu-Horizontal">
<ul class="AspNet-Menu">
Try adding AspNet-Menu-Horizontal to this style setting.
.AspNet-Menu-Vertical ul.AspNet-Menu li
{
width: 100%;
}
Also experiment with removing Menu ul.AspNet-Menu from this style setting. It appears you are limiting the ul width to 150px. but it should spreak the entire container. If 100% does not work, give it the width of the container.
Menu ul.AspNet-Menu li.AspNet-Menu-WithChildren li.AspNet-Menu-Leaf
{
width: 150px;
background: #741619 none;
border: solid 1px black;
border-top: 0px;
}
Hope this helps,
rinze