--- SETUP ---
Basically, change the variables, x and y to your liking.
If you want you can also change nDemonicFrame:SetPoint("TOPRIGHT", x, y, UIParent);
to something such as nDemonicFrame:SetPoint("CENTER", x, y, UIParent);
Notice that I change TOPRIGHT to CENTER.  This will set the message to appear at the
center of the screen.  If we change x and y to 0 and 0 with it set to CENTER we will
get our demonic portal messages in the center of our screen.  Below is from WoWWiki:

 * "TOP", "RIGHT" "BOTTOM" "LEFT": the center-points of the respective sides.
 * "TOPRIGHT", "TOPLEFT", "BOTTOMLEFT", "BOTTOMRIGHT": corners of the frame rectangle.
 * "CENTER": the center point of the frame rectangle. 

--- CREDITS AND OTHER INFORMATION ---
Still my first AddOn and still learning Lua so I'm always open to suggestions.
I'm trying to keep this as light weight as possible.  The version before this
was using 2.8kb of memory this is using 6.2 but it tracks the information a
little better and that annoying problem with it getting shown as on cooldown
whenever you cast anything is fixed.  Hopefully, people that do like this mod
will be okay with the slight increase in memory usage.

If you don't like my coding style, oh well.  I've developed my own style and
I've used it for over ten years.  It's not changing now.  :)

The following people I've at least looked at their code and how they did things.  

WoWWiki(lol)
Tukz
Nightcracker
Kjado