That might be an issue depending on the program used and what is being filtered out. If it is set up to disable/not allow images, java, flash, or other random things, it can definitely mess with some stuff. If there is an "unprotected" computer in the house, you can test the site on there. Best bet would be to ask your parents (or whoever controls the filter) to disable EVERYTHING so you can test out just this issue. If it works, then you know that's the problem.