Now that you mention it, I did have trouble with it on some other computers. It just doesn't seem to load. I never did find a solution.
And for those of you that it does work for:
LaGuardia:
http://www4.passur.com/lga.html
Newark:
http://www4.passur.com/ewr.html
JFK:
http://www4.passur.com/jfk.html
St Petersburg/Clearwater (Tampa):
http://www4.passur.com/pie.html
Hope it works.