Best answer by Chris
So if you have the Play:5 hooked to your actual router via Ethernet cable the system comes up. ARe you then able to add the second Play:5 (going to settings...add room). So that then you have both working but one Play:5 is hooked to router.
While its up you go to controller...settings...advanced.... wifi setup and follow through the wizard. Once wizard is done you unplug your play:5 and reboot it. Give system about 3-4 minutes then open controller and system should be up (If asks you always chose connect to existing system then).