TP Link 703N configuration

Anyone know how to configure a 703N into client mode using the Luci interface? I want to be able to plug the ethernet jack into an arduino ethernet shield and get access to the wifi on my local network. I can only find instructions that use other methods than the Luci web interface for configuration of the TP 703N.

I am tantalizingly close. It works as a client off the wifi network, in that I can plug a laptop into it and get access to our wifi through it. But I can't figure out how to configure it so that it connects to the LAN, so that I can communicate with the Ethernet card on the arduino using one of the computers on the LAN.

I can plug the 703N into a laptop and configure it over the Ethernet connection, but I'm not knowledgable enough to know how to configure it correctly.