Hi, if you want to use the button object for your radio buttons, you can do this
Create three buttons: button1, button2, button3, set the type for all buttons to checkbox.
Event\Actions:
button1 - On clicked >
button2 Set unchecked
button3 Set unchecked
button2 - On clicked >
button1 Set unchecked
button3 Set unchecked
button3 - On clicked >
button1 Set unchecked
button2 Set unchecked
Or you could do it with sprites. . . .