Kartris is designed to allow new payment systems to be added without changing code or making changes to the database.

Unzip the files and copy the folder for the payment system to the 'Plugins' folder in the Kartris web. Then go to 'Configuration > Payment and Shipping Gateways'.

Click the 'Refresh' link and Kartris should find the new payment system. Once in the list, you can click 'Edit' to change its settings. Each payment system has its own settings, which vary from system to system. This information is not stored in the database; instead it is stored as XML within the payment system itself. This makes installation simpler since you don't need to add new database records for each new payment system.

If you receive an error when you try to save changes to the settings of a payment system, it is most likely caused by there not being 'write' permission to the 'Plugins' folder. You will need to adjust this from the 'properties' dialog in Windows Explorer, or (if on shared hosting) contact your host's technical support team.