Integrate this script into wordpress

Hi all, I have a PHP script that I would like to incorporate into my wordpress site. It is a golf handicap script.

Basically I want a user to be able to log in and be able to edit and update their latest golf scores which will then update their handicap.
So what I need to know is, how do I get this script to work in with the wordpress users and so that it will save their handicapping info.
I can get around editing themes and plugins alright but this one is a bit beyond me.

Any help is appreciated.

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