For #2, ou should disable the inbuilt firewall and just use firestarter
#3, about the freezes, check you system logs for clues, but it definitely sounds like a bug that you should report to the fedrao bugzilla
You last point about uptime. You should be aware that you are running a test release. Test release exist for testing and reporting bugs. There are usually a lot of bugs to be found, so the system is not very stable and is not recommended for production. That being said, it may be hard to have a 24/7 uptime if you're using a test release.