I have a dual head system, with the secondary monitor located to the left of the primary one (hence having a negative x coordinate).

Now, when the pelude window(s) show, the algorithm that moves the windows out of the way gets confused. When I try to move the prelude window on the primary monitor out of the way, it remains stationary. Instead, the prelude window on the secondary monitor is moving.

So in summary:
- Two prelude windows are shown, one with negative coordinates (correct), one with positive coordinates (correct)
- When moving the mouse in the primary monitor (positive coordinates), the leftmost prelude window moves (negative coordinates, not correct)
- When moving the mouse in the secondary monitor (negative coordinates), there is no effect on either prelude window (not correct)

Sorry for spelling it out this far. I was not sure my initial explanation was clear. In fact, I'm not even sure I'm clear now :-)

Fixed.