Tina Clarke, MS MVP Expression Web has just added an in depth tutorial on Expression Web’s SuperPreview feature to her Any Expressions Design site.
Expression Web SuperPreview is a brand new feature within Expression Web 3.0 Included also is Snapshot which is a sort of mini preview alongside your Design and Code Views. The Expression Web SuperPreview Tutorial along with its companion Expression Web SuperPreview Starter Kit go indepth and touch on almost every aspect of the application and the methods you can employ to find coding errors and how to fix them.
Read the full tutorial: Expression Web 3.0 SuperPreview. Make sure you also download her Expression Web Stater Kits so you can follow along with the tutorial. While you are there, you might want to check out her other tutorials and her collection of EBooks for Expression Web, many of which are F REE. Great job Tina!