When setting up your storefront, you can choose between three primary payment providers - Stripe, Adyen, or Uscreen Payments.
Now before you setup Adyen, note that you must have a Live Adyen account. When you create your initial Adyen account they will provide you a Test account.
You'll need to apply for a Live account which can be done directly in their software. Attempting to connect a Test Adyen account to Uscreen will throw an error.
Once you've been approved you can add the Uscreen integration.
Navigate to Settings > Payment Providers and under Adyen click Connect Account.
You'll be prompted for your Adyen API Key, Adyen Merchant Account, and Adyen Origin Key.
Your API and origin keys are found in Adyen under Account > Users. You should see a System user call Web Service.
Click that user and then you'll then need to Generate an API key and an Origin Key.
Make sure you copy your API Key before saving it, as once you save it, it's no longer copyable. If that happens, just generate a new one.
For the Origin Key, you'll paste in your storefront URL to generate the key. If you change your Uscreen domain later, you'll need to regenerate this key.
Lastly, when you create your Adyen account you'll be asked to create an account name. This is not the same as your merchant account that we require. If I click my account in the top right, I can see that Adyen created a merchant account for me by simply appending ECOM to my existing account name:
Yours should be similar, so when Uscreen asks for your Merchant Account, this is what we're after.
Once you've got all this pasted into the Adyen popup window in Uscreen you'll be connected and can start collecting payments via Adyen.