In order to construct a UI you could either use Polymorph or Spec.
For Polymorph examples try in a workspace:
UITheme exampleDialogs.
UITheme exampleBasicControls
For a Spec tutorial have a look at:
Bahman Movaqar, Spec - Part I: The Basics.
The Preferences Browser is replaced by the much nicer Settings Browser which can be found in WorldMenu > System > Settings.
And you can display a method’s senders in Nautilus (the new standard system browser) when you right click on a method name in the method list via the context menu.