So, for everyone else reading this....
To turn UPNP Off in Elite's Network setting, edit the following files for Horizons and Odyssey.
Odyssey: "X:\Your Installation\Elite Dangerous\Products\elite-dangerous-odyssey-64\AppConfig.xml"
Horizons: "X:\Your Installattion\Elite Dangerous\Products\elite-dangerous-64\AppConfig.xml"
AppConfig.xml
<Network
LogToDebug="1"
Port="0"
upnpenabled="0"
LogFile="netLog"
MaxUpRate="750000"
DatestampLog="1"
ProtocolOffset="0"
InternalProd="false"
BytePadding="3"
Oodle="OodleDictionary4.bin"
Also edit this file to insure UPNP is off in Elite Odyssey and Horizons.
"C:\Users\Your User\AppData\Local\Frontier Developments\Elite Dangerous\AppNetCfg.xml"
AppNetCfg.xml
<?xml version="1.0" encoding="UTF-8" ?>
<AppNetCfg ip="19x.14x.8x.21x" upnp="false" router="8" />
Note: x's in IP are to obscure my gateway.
Creating a Router Port Forward Rule: (IPv4 Router Rule set to "Port Forward" port 5100)
Do not confuse "Port Triggers" with "Port Forwarding". Your router may have both options. You want "Port Forwarding".
In general, these are the settings for your router.
Description: Elite Dangerous (<<Give the Rule a Name)
Inbound Port: 5100-5100 (<<Sometimes called "Port Range". Enter the same number in both)
Type (UDP/TCP): Both<(use both)
Private IP Address: 192.168.15.3 (<< Your Static Game Machine IPv4 Address)
Local Port: 5100-5100 (<<Sometimes called "Port Range". Enter the same number in both)
You may have a "check box" on your Port Forward page to "enable/disable" the rule.
Settings for IPv6:
If your router, ISP and OS support and use IPv6, you may see the IPv6 address auto-populated in Elite's Network settings. (If not, you will need to edit Elite's "AppConfigLocal.xml" file to turn it on. You need to edit this file twice, or copy an edited version of this file to Horizons as well.
Odyssey:
"X:\Your Installation\Elite Dangerous\Products\elite-dangerous-odyssey-64\AppConfigLocal.xml"
Horizons:
"X:Your Installation\Elite Dangerous\Products\elite-dangerous-64\AppConfigLocal.xml".
In the setting listed below. You cannot cut&past the one below, because your "UseNicGuid=" will be different.
AppConfigLocal.xml
<?xml version="1.0" encoding="UTF-8" ?>
<AppConfig>
<Network Port="5100" IPv6="1" IPv4="1" IPv6Port="0" ReportSentLetters="1" ReportReceivedLetters="1" VerboseLogging="1" UseNicGuid="{00000000-2D42-4E08-A213-BB00000000}" />
<Journal Address="0.0.0.0" Port="0" />
</AppConfig>
Note: "1"=On, "0"=Off above.
Note: By editing the network files for both Odyssey and Horizon, both iterations of the game will benefit from these network connections.
Elite's Network Settings in Odyssey and Horizons:
If your router port forward rule is active and your network firewall is not blocking it, you should see this in Elite's Network Setting's with the port number of 5100 auto-populated in the "Mapped Port Number". As well, you will see Router Type set to "Port_Restricted" and the same port number appended to your computer's static IPv4 address. You will also see your "Internet address" (ISP Gateway) with the port number appended.
So, All of this happens with the settings in your router to do port forward correctly. If done correctly, you should see these settings in Elite's Network Settings. Editing the files above, FORCES Elite's network settings to be used.
IPv4 Static Address Settings for your PC (Game Machine):
Your computer (the one where the game is installed), must have a static IPv4 address. You can set one directly on the network adapter through Windows, or you can have your Router's "DHCP Service" issue IPvX addresses to all devices and have your Router "DHCP Reserve" an IPv4 address for your game computer, (based on your machine's MAC address), so your computer will always get that IP address.
Now, back to the discussion of security issues over UPNP......