I initially fired up the Draytek and clicked PPPoE Passthrough for Wired LAN. Then I started the WNDR3700 and went through set up. It then seemed to be able to connect to the internet fine.
However, The Draytek was by default at 22.214.171.124, which made the router go to 10.0.0.0. I decided that I'd like the router to be at 126.96.36.199 to be consistent with all the usual discussions etc. So I changed the Draytek to 188.8.131.52, restored the router to factory settings and went through set up again. All seemed fine, except the Draytek just wasn't Connecting successfully to the internet.
Any idea what I've done wrong here?
I can supply details/screenshots if needed and you point me to the required settings.