CorelCAD 2020 User Guide ... is there one available or best to use Graebert free pdf for ARES Commander ?

Just bought CorelCAD 2020, ... when clicked on icon for plug ins it took me to a Graebert site that outlined their products including ARES Commander and invited me to register for newsletter which I done, ... it then provided a free .pdf copy of a User Guide for ARES Commander wrote by Ralph Grabowski.

Would like to use latest most accurate USER guide / manual to learn how to use CorelCAD 2020 properly, ... and found Corel online offer only a User Guide for CorelCAD 2016.

Can anyone confirm, ... A - what differences there are between 2016 and 2020 versions of CorelCAD, ... and B - what differences are there between the CorelCAD 2016 user guide and the Graebert free pdf guide for ARES Commander offered online ?

In an ideal world I would like to buy a printed copy book for CorelCAD 2020 but cannot find any online, ...?

Such a pity as few years ago I bought a great book on Corel X8 what was recommended on Corel.com website and published by Mc Graw Hill.

FYI, ... raised a support ticket to Corel on this, ... and response I got was a link to this forum ...

Paul