I cannot get my custom layouts to show up in the application builder. I've followed the steps in the help documentation and modified the Layouts.xml file (which I don't think is mentioned in the help, I had to find that on the forums) but nothing has worked. I've uninstalled and reinstalled the viewer and extensibility package a bunch of times but am getting nowhere. I've even gone into Builder/Templates/Default/Config/Layouts and just made a direct copy of one of the templates in there with a different name, added the entry to the xml file and it still didn't show up. I'm out of ideas.
This is my first run with the viewer application... so I don't know, maybe I'm working in the wrong directories or something, I can't figure it out.
I'm on a Windows 7 machine, version 3.1 of the viewer and extensibility SDK, Visual Web Developer 2010 Express (could not get the viewer template to show up in 2012), Expression Blend Preview for Silverlight 5. The Silverlight 5 toolkit is also installed.
Any help is greatly appreciated!