Yes, you need to relocate it.
Switch it to DHCP and put it on the 192.168.80.0/24 network, let LMCE discover it and add the shares as appropriate
In the admin console you need to go to Advanced->Network->Firewall Rules.
Here you can either turn off the firewall completely and it will just route straight through to the internal network like a normal router and your external network and internal network will be able to communicate freely. However, note that if you do this, you will not be able to use the port_forwarding functions of LMCE. These will be needed, typically, if you want to publish something on your internal network to the Internet, like a website. Or if you need to have other kinds of inbound connections to the internal network, eg if you have a bittorrent client on the internal network, for maximum performance you need to forward the port.
Alternatively, you will need to leave the firewall on, and allow only the ports you need through it. This depends on what you want to get access to through the Core.
Basic filesharing is typically on port 445 and perhaps 139 if using Windows. You may need to add others if you want to be able to browse your network neighbourhood. FTP - ports 20/21, ssh-22, web browsing-80, remote desktop-3389
Also, you will also need to add a static route to your broadband router that tells it how to get to the 192.168.80.0/24 network via the Core's external IP address. This will allow clients on the external network to get to the internal network.