How to add a payment gateway to my shop? 

In the administration in Settings -> Modules -> Search for GP WebPay Payment Gateway module -> Click on Enable module. This will pre-write your email with the monthly amount approval. Send the email to info@kvikymart.com, along with your details, see point 2. 
You will receive test data from GP WebPay after completing the steps they sent you. Together with the confirmation email, please send us: 
accesses to the testing environment, 
Merchant ID (merchantNumber),
the test public key (GPE_test_public_key.zip) and the test private key, which you will get from the GP WebPay interface.

Remember to insert both test keys (public and private) in the GP WebPay test environment administration.
For the private key, also send us the password you choose.
We will make a test payment and inform you. 

Contact GP WebPay to obtain production data. You will resend these to us, they are as follows:
Accesses to the production environment
Production public key and production private key

Again, remember to enter both production keys (public and private) in the GP WebPay production environment administration.
For the private key, send us the password as well. Preferably choose the same one as in the test environment. 
We will start the payment gateway on production and inform you.

After GP WebPay confirms that the gateway is working, set up the payment method for each shipment.