About new windows...

[Kobushi no Kami]

Hi. I want to open a new window using the newwindow:windowopen command. It works, but the new window appears randomly on the screen, most often at the lower part. I want it to be opened in the center of the screen.
Is there a way to do this? Thanks.

[Kobushi no Kami]

Thanks. Only one more thing: where do i put that code? Thanks.