The team blog of the Expression Blend and Design
To access the User Guide, make sure you have the latest version of Deep Zoom Composer installed and go to Help | User Guide or press F1:
If you reached this post via the User Guide link found in the Welcome Screen, rest assured that we will fix that bug in the near future. Clicking the User Guide link should open the user guide and not take you to a blog post :)
Can I add deep zoom application in the website and how?
YOU ALSO REACH THIS POST VIA www.microsoft.com/.../details.aspx if you click the "DeepZoom Composer" link in the description. So where is the online user guide or a download file for it?
msdn.microsoft.com/.../cc295790.aspx that had been posted by Kirupa in the comments no more contains the user guide