In the post you reference ray was talking about closing the info windows when using links to change the active marker, not closing the info windows as a general rule.
The issue being discussed in that thread was that when using links to change the focus address, it would leave the initial info window open, and also open the new focused info window.
to close the info window on page load, find the following code:
// open info window for default address
if (isDefault) {
infowindow.open(map1,marker);
map1.setCenter(point);
}
and change it to:
// open info window for default address
if (isDefault) {
//infowindow.open(map1,marker);
map1.setCenter(point);
}