After having my FSHost go down after my last post, I had to dig even deeper into this..
To answer your question:
My Internal IP address by default was 192.168.1.11 on my linksys router software. I had always thought that was the one that I was supposed to forward to, since the software set it up that way. After I ran IPconfig, I saw that the internal IP address was actually 192.168.1.100. I am absolutely no expert at this, but I take it that the online sever is connecting to my FSHost via the external IP address, then needs to forward the data to an internal address. I think that the problem of no connection (from "Client" to "Host") was simply that my FSHostSpy was trying to route data to an incorrect IP address internally , 192.168.1.11 vs. 192.168.1.100.
Incidentally, during all of this, I knew that my FSHost was set up correctly because I was able to connect to the FSHost with FSClient, however couldn't connect to FSHostSpy to see my or other sessions.
Back to my FSHost crashing after my first post. I tracked this down to uPnP needed to be set to disabled. I spoke with a network expert friend of mine, he said that this one of the first things that he does when setting up a wireless router. "Always causes problems" he said. After this was taken care of, my FSHost/Client/Spy software has run 24/7 for about 2-3 weeks now.. (which is why I haven't posted a response for so long

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Thanks for the response and for the cool software!,