Konica C352 Printer Driver change paper size

[123eprint]

Hi I just got a Konica C352 printer and need to change the paper size to a custom settings but the printer driver does not let me change them. I am including a link to a screenshot. As can be seen the settings are dim and can't be changed in the box on the right. Any help would be greatly appreciated. I am using version 03.01.01.00
Thanks

Screen Shot link http://s1085.photobucket.com/user/12...a/eer.jpg.html