Can DWF files created by DWF Toolkit 7.0 be read by Autodesk DWF Viewer 6.0 and Autodesk DWF Composer 2.0?

In short the answer is Yes. See the explanation that Scott Sheppard at Autodesk posted to the Discussion Group. 2005-07-25 Update: More about it by Shaan Hurley: http://autodesk.blogs.com/between_the_lines/2005/07/new_dwf_toolkit.html