I'm already using this component with a custom made extension for a local payment server a few years ago.
currently I want to upgrade and want to use the already available extensions for a payment gateway.
can anyone tell me which gateway I should use in Belgium ?
We don't know any special payment gateways which can be used for your own country. I think you can use PayPal or maybe Stripe (I am not sure if Stripe is supported in your country)
You can check to see what payment gateways are popular in your country, and let us know. We will then tell you whether that gateways are supported in our products