> I would like to use the preferences and 
configuration 
> details from the previous version after  I upgrade. 
> Can this be done, and what is the best way to do it? 

You can update/continue a project created with 2.x 
releases with HTTrack v3.x without changing anything - 
just select the desired project and continue or update 
it as you would do with a project created wirh 3.x!