I'm not using the Engenius but the ROGUE for this test. The router has an auto negotiate feature. My set up ssitches to VZW 3G/4G if I lose the WAN connection for 30 seconds. In testing from my office the usable RF range on medium power with the MBR500 router was 200 feet. DHCP is assigned/served by either the Verizon 3G/4G modem or the ROGUE and rebroadcast through the CradlePoint MBR500's WiFi. So far it is flawless. I disconnected my Wave EC/HP/RP to try a lower cost solution using the Wave ROGUE. There is no practical LAN or WAN limitation if the CATe distance is within specifications unless you have a 12VDC POE to the Bridge unit ( I do in this test with a ROGUE 45') if it is 12VDC over the CAT5e you are limited to about 100 feet between the POE and the Bridge unit. That mimitation has nothing to do with the ROUTER on the boat.
Bill
Bill