The summary at the end of the Compatibility Check displays a summary of the device / interface you've chosen. The summary is an assessment of how compatible it is with PeakHour.
The most important thing here is to check that the graph in the bottom right represents the activity you're trying to monitor. If it is flat and you think it should not be, it may still be that your router is not correctly reporting traffic.
Here's a description of the checks and their meaning:
|Responding to SNMP / UPnP||The device was able to be queried with either SNMP or UPnP (depending on what was chosen).|
The device is reporting bandwidth passing through the chosen interface. This usually indicates that the device/interface is up, connected and working.
Note: It is possible for this to be No but the device/interface is still actually working. This can happen if no traffic is detected on that interface whilst on the previous screen. If you think this might have happened, try pressing Previous and waiting longer or generate some traffic over that interface so that PeakHour is able to detect it.
See this document for more information: High Capacity Counters.