Hi
Although I am writing this reply to you using an Apple MacBook running Leopard, I am afraid that Question Tools Editor and server software runs on Windows only at present.
It is quite possible to take exams on an Apple Mac using Firefox or (we think) the version of Safari that comes with Leopard (previous versions broke a lot of standards, but Apple appear to have fixed this).
We are working on an Apple version for the next release, but I am afraid this looks like it is at least a year off at present.
Hope this helps (as far as it can).
Regards
Paul Booth
Question Tools Support