I encountered the same issues however it's all fixed and working fine. I was trying to connect my TC to my existing Router and create a separate Network. Here is what I did to make that work.
1. Factory reset the TC
2. Connected an eathernet cable from the existing Router to the WAN potr of the TC (the one closer to the power-code)
3. Ran Airport Utility from Macbook Pro
4. The TC will appear as a New device.
5. Setup and say you would like to create a new Network
6. Go through the steps and viola you will see the green light.
I now have two Wireless Networks (one from the Original D-Link connected to the Modem and the Other from the TC connecting to the D-Link) Both works well.