This is a very good class, but it has a little problem yet. The problem is in the way you access the elements. There is no way to access a simple file, starting by the root and going down element by element. You just can access the last entry ($root->curtag).
It would be very usefull if you add something like $root->getChildren, this function would return an array of children, an then you can access the inner elements.
Think about, and please reply this message if there is a way to solve my problem.