This won't answer your question on Dabbler exactly, but might be of some
use. It includes handouts, a small gallery of student art and a FAQ. (It
is the _only_ site I found in 5 search engines !!! that includes tips and
teaching hints for Dabbler).
Also has similar information for PhotoShop and Adobe Illustrator. The FAQ
includes some information for several other programs.
Art Teachers: http://www.geocities.com/EnchantedForest/Dell/9575