"variable '_Points' conflicts with a member implicitly declared for property 'Points' in class 'Player'."
I'm not sure about this but it sounds like it's trying to create auto-generated property procedures for you and it's creating a variable named _Points behind the scenes. Then when you create your variable with that name, it's getting confused because there are two variables with the same name.
(If you're feeling daring, you could peek inside the auto-generated code to see if there's a variable named _Points in there.)
Try commenting out the variable. Then go to the end of the property declaration and press Enter to see if the code editor can make the property get and set procedures. If so, uncomment your variable and you should be back in business.
If that doesn't work, let me know and perhaps email me the project and I'll look more closely.