I find it extremely strange (worrying in fact) for webassist not to have clear instructions on how to remove their software (only).
It seems that you are suggesting totally disabling or destroying Dreamweaver by renaming the configuration directory ? !!
So I only want to try Adobe's supplied method of Extension Manager, I have screenshots of the errors after Extensions Manager says DataAssist is uninstalled BUT on launching Dreamweaver again I get two error screens...
"Unable to find file WA_Memento.htm in the Configuration?Floaters directory. The floater will not be shown."
"Panel 154 could not be created. Removing it fro the list".