@adamlevine I assume you are familiar with the Pimatic Development documentation and you already have a plugin development project setup.
How do I add another Plugins to the list of Installed Plugins?
The starting point is to setup a project on github. When you are ready to release your plugin you will have to publish it to npmjs.com using npm. Pimatic will automatically pickup published plugins from there. See also the Development Documentation.
Since it is the same plugin & name their is only one & I need 2 listed (how do I add another one).
1-How do I get it to be listed twice so i select it for another address 513 (Universe 2) in the Installed Plugins.
You cannot run the same plugin twice. My suggestion to you is to implement the DMX Control using a pimatic device type. This way you should be able to create, modify, delete universes at runtime without having to restart pimatic.
2-Will DMXControl work with 2 Identical Enttec open dmx USB Devices?
Well, I guess that depends on your implementation. What is the starting point for your implementaion. Do you use node-dmx or are you targeting at a low-level implementation using a serial line driver like node-ftdi?
Did you also see earlier posts on DMX Control?
"It always takes longer than you expect, even when you take into account Hofstadter's Law.", Hofstadter's Law