WowAce

What steps will reproduce the problem?
Just have UIParent to not cover all the screen.

What is the expected output? What do you see instead?
When you drage a frame it should stay where you release your mouse button.
Instead it move the same number of pixel the UIParent is to the left size of your screen.

What version of the product are you using?
1.1 r11

Please provide any additional information below.
You should replace line 160 and 165 by those ones:
setStorage(frame, "x", x-UIParent:GetLeft())
frame:SetPoint(point, frame:GetParent(), point, x/s-UIParent:GetLeft(), y/s);

Now I'm intrigued.. why would you move UIParent?

And perhaps more importantly - WHEN do you move UIParent? Do you want windows to move when the UIParent moves or not? Why? Why not?

I move UIParent beacause I am on eyefinity configuration (3 screens) and I want my interface to stay on the center screen. It's done automatically in Tukui when it detect you resolution.