GoCardless
To set up the GoCardless connector for your users, you will need a Client ID and a Client Secret. You get these by creating a new application in GoCardless.
Preparation
When creating your oAuth App, you will need to provide your Cyclr Partner Service Domain so it's best to have that information to hand before you begin.
This is specific to your instance of Cyclr and can be found in your Cyclr Partner Console under Settings > General Settings > Service Domain.
Your Cyclr Partner may have been setup with a default Service Domain, but this can be changed if you would prefer to remove mentions of 'cyclr' from it. Contact Support for more.
Creating a oAuth App
There are instructions on how to do that here (https://developer.gocardless.com/getting-started/partners/connecting-your-users-accounts/#creating-an-app ).
When asked for a Redirect URI, enter the following: https://[Your Cyclr Service Domain]/connector/callback
Cyclr Setup
From your Cyclr Console, click the Connectors option along the top then Application Connector Library, find GoCardless - you may need to use the Search box to locate it - then click the Padlock button and paste and save your values there.
You should now be able to successfully install a GoCardless Connector.
At this point it would be a good idea to install a Connector and run a test against one of the Methods, just to make sure the authentication process has been completed successfully.