Another Deadlock based mod called ActionControls used the following method since the SetMouseLock change. When you lock the mouse, it draws a crosshair at the location that the mouse was at. So without using AHK, you can at least see where your mouseover point is. I had adapted Lockdown (because it works the best out of any of the other addons) to use this functionality, as I was not using AHK along with it before tonight.
edit: Using this method, you could eliminate the need to set the reticle position in both the lua and the ahk.