Hello,
I have a E3272s modem connected to a TP Link WR710N and running Chaos Calmer.
Everything works great (even on the 4mb version of the TP-Link also with PPTP client and Watchcat plugins installed) the only thing that I have problems with is accessing the modem from WAN. I forwarded the port 8080 (doesn't really matter which) to 192.168.1.1:80, where you access the modem over LAN.
When trying to access, like this: "http://domain.com:8080"
But I get redirected like this: "http://192.168.1.1/html/index.html?url=domain.com:8080"
Other port forwards (e.g. VNC, HTTP, FTP,...) work nicely.