Modules are "blocks" of code that perform specific functions in the Miva Merchant admin interface. If you write a module you can have it show up almost anywhere in the admin interface so that it can be enabled and configured. For example, logging modules control the creation of log files and show up in the Logging Settings screen.
The System Extension Settings screen is kind of a catch-all for modules that don't belong anywhere else. There are three modules that show up in this screen by default, but if you install third-party modules they may also show up here.
Please see Payment > PayPal Express Checkout and/or Payments Pro for instructions on configuring this module.
Please see Payment > PayPal Payments Advanced and/or Payflow Gateway for instructions on configuring this module.
buySAFE allows your customers to add insurance to their orders during checkout
Select the buySAFE tab.
4.1. Check the "I accept the buySAFE End User License Agreement" checkbox.
4.2. Click the register now button to go to the buySAFE website and create an account.
4.3. Enable buySAFE Bonding. Adding buySAFE to your store requires changes to some template code.