Q: Is our permission to access site data limited to the date the site owner installed our app, or do we have access to historical data?
A: The permission the site owner gives you is not limited by date. When a site owner installs your app, they are giving you permission to all the requested data - in the past and upcoming data.
(This also means that if the site owner uninstalls your app, you will no longer have access to any data, including events that took place while you had permission)

Q: Is there a test account or payment method we can use to test different payment options?
A: Sadly, no. We are working on it. In the meantime, you can start with the offline transaction option to get started with the API.

Q: What is the most reliable way to use pagination in your API to get a set of transactions that occurred during a given timeframe?
A: Set an end date, order by activity date, and continually increment the offset by the limit until the total is reached.