Flash Player 6 to 5 Conversion problem

I am having a problem converting a movie originally created to play in flash player 6 to 5. The movie is a quiz that randomly selects questions and their corresponding answers from an xml file. It will also accept a variable for the number of questions to include in the quiz. I am developing with Flash 8.
I have changed the original movie by removing all of the field text instance names, added the randomize function, added a duplicateMovie function to create the answer boxes, and added a running score box.
All of these modifications work fine when the movie is published to flash player 6, however, when published to flash player 5, I get NO action script errors, the movie loads with a question and corresponding answers, but when an answer is selected, it does nothing. I have traced the problem and I know the “answer check” function is being reached, however it will not advance the movie.
I have reached my limits on troubleshooting this problem and am looking for advice on how to either fix it or what direction I should be looking in to find the problem. I have attached the movie and xml quiz in a zipped folder. Movie is 174kb when uncompressed.