Here is the procedure to enable customer reward points.

1. Go to Maintenance>Resources and select the resource payment.receipt.tabs
2. Uncomment the line

payment.addPayment("Points", "payment.icon.points", "points");

3. Select the resource payment.points and set the reward point values.
Example for setting reward point values:

pointsin.setValues(200.00, 1.0, 100.00, 0.5);

Here for a minimum purchase of 200.00, customer earn 1 reward point. For each additional 100.00 of purchase amount, customer earn 0.5 point.