The attached zipfile includes a sample application that contains a sample WPF application with a list-box that contains three textblocks for each item. The sample script traverses the items in the list and each of the controls in each item.

We use a custom function to access the controls:

function DumpUIAChildren(objRule, rootObj)
 Tester.Message("Name: "+objRule.objectName(rootObj)+" objectClass: "+objRule.objectClass(rootObj));
 // Learn the child as 'SeSObject'. Now we can use standard methods (Do... Get... Set...)
 var sesObj = SeSTryMatch(rootObj);
 // .highlight() is undocumented but very useful
 var ccount = objRule.childCount(rootObj);
 Tester.Message("# of children: "+ccount);
 for(var i=0;i<ccount;i++)
  var childObj = objRule.childAt(rootObj, i);
  DumpUIAChildren(objRule, childObj);

Once you have this function added to the Test.user.js file you can use it with your learned ListBox object:

 var list = SeS('List');
 DumpUIAChildren(list.rule, list.instance);

The full source code is in the attached zipfile.