Reading Checked property

Hi, Probably being stupid (again), but I can't seem to read the checked property of a button in a buttonset where all buttons are of button type jqbtCheckBox. The individual buttons' checked appearance are being changed on the page, but when I come read the value of checked for each button, I get the original value that was set in the Embarcadero designer. The C++ code I am using to read the first button is ChartPropertiesIWCGJQButtonSet->JQButtonSetOptions->Buttons->Items[0]->Checked. Is there something I am missing. The same code seems to work for another button set that I am using with radio buttons.
Thanks in advance.
Richard
Thanks in advance.
Richard