KUKA LWR4 Payload Diagram understanding

Hello,

I have read the documentation of my LWR4 Robot but for me is not clear how to understand the payload diagram. I need to understand it

because I want to create a tool-head for the robot. Could you please explane me how I can read and undestand the attached diagram.

What is the Point marked with "P"?

Thank you in advance!

Best regards

Thank you for your answer. Want to ask you what you mean with CG?

Quote from amex

Thank you for your answer. Want to ask you what you mean with CG?

I have understand it - CG = center of gravity