RadioGroup.ItemIndex
I did look at that WP, thanks, but when I tried to set it to '1' (selecting the first button as default) it threw up an error 'Out of bounds 0...-1' so I had to resort to setting the 'checked' property of the first button to 'true'. - I did see that all others were automatically set to 'false'.
Am I to understand that it will be set at run-time to 1,2,3 or 4 (in the case of a group of 4) or even 0,1,2 or 3 so I can do a 'case RadioGroup.ItemIndex of ...' ?