In lieu of photoshop cs6 not having "Live Shapes", you could use this Corner editor script to change the corner radius after drawing a shape.
https://photoshopscripts.wordpress.com/2013/02/03/corner-editor-photoshop-script/
In lieu of photoshop cs6 not having "Live Shapes", you could use this Corner editor script to change the corner radius after drawing a shape.
https://photoshopscripts.wordpress.com/2013/02/03/corner-editor-photoshop-script/