If you have the port forwarding RPM installed, you should just need to go to the Server Manager, and tell it to forward external port 2000 to port 80 on 192.168.27.65. I have absolutely no experience with 5.5, so I can't comment on the issues with 5.5 and port forwarding.
As for the other apps, you just need to do the same thing, kind of. You just need to figure out which ports those apps use and tell it forward those ports to that same port on 192.168.27.65. Some programs, like most of the IM programs' file transfer stuff, use dynamic port numbers. You'll have to go into the program, and specifically tell it to use a certain port(s) as well.