Animates position isn't centered

[karneaud]

I'm using your boxy framework here http://www.thenextfifty.tt/

when I click "submit your own" to open the dialog and "close" it then click to open it again the position keeps changing. repeating this process drives the dialog box out of view for which the html,. body is overhidden

[xero]

same here. calling the show method repeatedly will drive the box off the screen. calling center after show fixes the problem.