Timothy, I used the original Quiz Timer Hack and found that it would work with IE, but would not show the time for any Mozilla (Netscape) or Firebird users. A friend I work with looked at it and found something IE-specific in the coding in the mod/quiz/attempt.php file hack code. I am not sure what he changed, but it now works for me in those browsers. Of course, that may not what your problem is, but in case it helps , I have attached my modified attempt.php file - what he changed was in the html that acutally shows the time remaining.
Hope this helps!