The Vannila example posted has various dtd and other tags on the top of various jsp file index.jsp , success.jsp, struts.xml etc or try to compare your app code with the Example1 posted in the same site. it should work then.
this problem is easy.you can do this:
new a folder named "namespace" in WebRoot ,then drag success.jsp in it.
the action result url will be change into <ApplicationContextRoot>/<Namespace>/<result location>;
for example :
your url will be change into <ApplicationContextRoot>/asdfasdfadsfasdf/success.jsp
obviously,it's wrong url.because you don't have a jsp in the folder named asdfasdfadsfasd