Monthly Calendar in WP Office X5 Perfect Expert Macro

Hi, I want ro change the content of Perfect Expert Macro of the "Monthly Calendar" from English to German. Can anyone tell me how to proceed? I've tried hard to find out all by myself but in vain. I need a detailed single step orientation in order to succeed. My problem; I don't find the Macro (location & name?). What can I do?
Best regards, Boy