List id: You can find the list ID by clicking the list in your ActiveCampaign account, then viewing the URL bar. It will look something like this: /app/contacts/?listid=19&status=1
API URL: Your API URL can be found in your account on the My Settings page under the "Developer" tab.
API Key: You can get it his way:
Send the Newsletter System name, the list id and the API key to Sovendus