A big THANK YOU to everyone for their assistance on this. I've managed to download the free version of Fusion 360 and made more progress in 24 hours than in a week with FreeCAD. I suspect FreeCAD is good if you already have knowledge of CAD/CAM but for me - starting from scratch, Fusion 360 seems much more intuitive. The only slightly worrying thing is when I went in the the Manufacture part of the program it came up with a warning saying, "available for a limited time only". I now have to move on to other more important niggles now such as why my machine has manufactured my first Fusion part with annoying lack of accuracy, 28.5mm wide should have been 30mm, 78.2mm long should have been 80 and 8mm depth should have been 4mm! I thought I'c calibrated the machine super accurately but it seems I have to go back to the drawing board on that one.

BTW, thanks Kitwn for the links to gear2motion and woodentimes I have been experimenting with the software by Matthias Wandel at www.woodgears.ca but I'll look into these other.