I have alarms working using the Raven XE your configuration file has been uploaded and saved into it. The only other change that was made was to disable 3G for the modem to work with our cellular provider (after talking to Sierra support). If a PLC gets disconnected for a short period it still does not re-connect unless the raven is disconnected.
DHCP is disabled under the LAN/Ethernet tab. Are there any other settings that can prevent the above.
Check to see if there is an IP address conflict on your network