Two things you need to change: First, declare and use the
http://xmlns.tibco.com/bw/process/2003 namespace in your XSLT code.
Second, remove the default namespace declaration (xmlns="http://www.w3schools.com") from your source XML, because XPath 1.0 interprets "/config/" in your example as "a config element not in a namespace" instead of as "a config element in the default namespace", which leads to its not finding any of your config elements.
I can't believe there's any point to the default namespace declaration in your example. But if there's a real business requirement for it, there are ugly ways to work around it.