Having trouble with flash gallery when repositioning

the gallery I downloaded from http://www.kirupa.com/developer/mx2004/xml_flash_photogallery9.htm
has a problem that I cannot solve
when I increase the carvas size to 1000 by 700, and I move the whole gallery to right at the center of the carvas, and then I test movie, it ceased working, when I undo the last step, it fix itself, I just don’t understand, I read through the code, nothing is really concerning the carvas size, but it’s just so weird, help!!