Hi Patrick,
I have reduced the RAM to 384 and now using the gateway in GUI-less mode. So far, it has been running for about an hour or so with no drama. I will let it run for a while longer just to test if it fails.
After I have finished testing this, I will go back into normal GUI mode and make the modifications you suggested and post back the results. So, give me 1-2 days before you hear back from me.
Thanks.