I am not sure if anyone of you aside from me has encountered this, or if this has been discussed some time ago on this board. But let me share this anyway..
Whenever you are trying to setup the DIR-605L for the first time (assuming that you already did the correct physical connections), you will get a setup wizard on the screen. Hit next then it will allow you to select the type of Internet connection you have on your network. Mostly, we would select Dynamic IP (DHCP) and leave everything else default. After hitting next, the screen would show that the router is detecting the Internet connection then after a few seconds, you will be redirected back to the screen where you will select the Internet connection type. If you would still select Dynamic and tried to proceed, the page will still kick you back to the previous window and you're stuck with that and cannot continue.
This is very bizarre for me but this is what it fixed it for me:
1. At the Internet connection page, instead of setting it to Dynamic, set it to Static IP
2. It will of course ask for the static information. Just make it up. For example, I set the IP address to 192.168.5.x, Subnet: 255.255.255.0, Gateway: 192.168.5.x, Primary DNS: 4.2.2.2
3. Hit next
4. A screen that says "The router is detecting your Internet connection" will again appear but after a few seconds, the network settings will show up. Internet connection status will be Not connected but you dont have to worry about it for now.
5. Save the settings, then you will be logged out
6. Log back into the router using the default credentials (admin, no password)
7. The network settings will again show up, Internet connection status is still disconnected, just click Manual Setup
8. And now you are inside the router page, you can now change the connection type to Dynamic
9. Do a MAC clone (only if necessary)
10. Configure the wireless settings
Hopefully this would help someone..