Click on the router in airport utility. There should be a text line that says STATUS. Click on it to read the status messages. Do you see any amber circles anywhere? On the drop-down that has the EDIT button, click on the ambert circle. IIRC it should be there..... But man I do hate that PoS 6.0
We must have different versions running. If I click on the router, all I get is the dialogue box for Edit or Updat - no Status line. If I click on Edit, there is no tab with messages. Also, the Edity drop down does not have any amber numbers or message line. I have OS 10.7.4 and AirPort 6.0.
The red number beside any device in Airport Utility indicates that the divice needs a firmware update. Click on the device and hit the update button. The firmware will update and the red number should be gone