This is a bug I've not seen often in Mac software except in Macromedia stuff. Parallels seems to be "remembering" the position of the VM property page window, which is nice. Unfortunately, if you last used the VM on your second screen then disconnected the second screen, you don't have a way to have the VM property page show up on the main screen afterwards. In other words, when reopening a previous VM, Parallels does its best to keep the old window position, neglecting to check whether said position is still in the screen visible space. Since people (especially on MacBook laptops) easily connect and disconnect screens and reorder their positions, the software should force out-of-screen windows within the screen space.
