Urroz asked me to make you aware that his old 2009 tutorials are the ones being posted at your download page
http://en.smath.info/forum/default.aspx?g=posts&t=561
rather than his new Oct 2010 versions that can be found at this location on your website.
https://smath.com/wiki/Tutorials.ashx

Personally, when I just downloaded SMath, it was those that I began reading only to find out that there are more extensive and updated ones available elsewhere.

Dave