What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
Hope this information helps.
They open fine in Internet Explorer but not FireFox.
I've tested it with Firefox and it works fine.
I checked also your form/s using Firefox and it's working properly. I don't see any problem in your form. I suggest logout to your account, delete browser cache and cookies then log back in.