Option 1:
Well, all you would have to do is change the word "posts" to "points" in the language file, and that's it as far as WWF goes.
Then you modify your game so that they can earn points, buy and trade points, etc. on pages completely outside the forum. You would simply have those pages do database calls that add or subtract points from the posts field in the WWF database. This would automatically update WWF with the correct number of points.
Option 2:
Create a seperate database field to store the points.
In WWF, you would add a line under "posts" that displays the "points." You would have to have it do a database call to get the points from the database.
Then you modify your game so that they can earn points, buy and trade points, etc. on pages completely outside the forum. You would simply have those pages do database calls that add or subtract points from the points field you created in the database. This would automatically update WWF pages with the correct number of points.