Quiz does not score with multiple swf's loaded

I have quiz that scores fine when played as a single swf.
However, when I load the quiz along with the header and navigation swf files that scoring does not work.

here is the main.swf that calls all the files together:

loadMovie(‘header.swf’, 50);
loadMovie(‘quiz.swf’, 10);
loadMovie(‘navigation’, 110);

Any help would be appreciated.