Can't access internet when connected through another router (ER-Pro8)

I have an ethernet connection in my building (witth a private IP address 192.168.1.x), and I wanted to use my ER8Pro to create my own private network that is not accessible by others in the building.  

I used the Wan+2Lan wizard to set up the router.   I plugged my building's ethernet cable into the WAN port (eth1), and my switch into eth0 and Unifi AP-lite into eth2.   It seems that my devices all get IP addresses from my ER8Pro, but they can't access the internet.  

Is it because the WAN port has a private IP address?  Or does anyone have any other suggestions?

THanks,