I'm in the stage where I am setting up my software. One thing that drove me nuts was the display numbering that Windows did.
Somehow my DMD monitor was set as display 1 and no matter what I tried, I couldn't change it.
After 2 nights of Google-ing, I finally found a solution. No doubt this will come in handy for others, so here it is:
Long story short:
To force Windows to configure monitors properly if the numbers aren't correct, you need to delete these two registry keys, and then add the monitors one at a time.
Hope this helps!