Hi Michael,
There are actually 2 areas that you can check to see what events are tied to a particular return status. The first one is where you link your events to a payment status under Module Config, PayPal Gateway, Form Completion Events. You can select the event and then choose from the options below what payment status should trigger the event.
Then, you can go to Admin, Event Viewer, make sure that Debug logging is enabled. Then when you start testing, you can come back here and see what IPNs are coming and what events are firing.
You can also create a 'Last PayPal Status' field on your field and link this here so you can see the most recent PayPal payment status that came in for this form record.
Candace