How to Run a Server on a Mac with OSX.
Ok so basically running a server on a mac is like running one on a windows computer. You need a map, a configuration file, and to know the commands. 
So include with this guide is a conf file which i suggest you put in /users/Yourcompname/ along with a map file in the same directory, that way they are both easy to access without having to memorize or retype long locations addresses. 
READ THROUGH YOUR CONFIG FILE AND CUSTOMIZE IT!!!!!!!! then when it asks you at the bottom for a map put "/users/yourname/mymap.bzw". Then it will look there for your map, make sure to change the yourname and mymap part however.  Once you've done that, you need the "terminal" this is located under you applications folder, and within the utilities folder near the bottom ( /applications/utilities/  ). Open that up, now you should get something like
"Welcome to Darwin!"
[name of your computer:~]name%"
once there you will be able to  run the server by opening you config file which you have already customized. here are the steps
First you need to change your directory, to change to any directory on your computer be it mac or windows type "cd" follow by directory extension. For the mac we would type
cd /applications/bzflag-2.0.2.app/contents/macos
depending on how you installed it the bzflag folder could be marker bzflag2.0.2.app or bzflag-2.0.2.app you can check in your applications folder to see the full file extension by clicking on "Finder in the top left hand corner, go down to preferences, and open that, there will be a check box marked show all file extensions" click on that and close.

So once you have redirected yourself to the bzflag directory you can do 3 things there, you can run bzfs which runs a server, or bzadmin which allows you to connect to a server without opening the bzflag client, or you can run the bzflag client.
First we will talk about bzfs and running the server. So you will need to have completed you config file, once done make sure it is in the directory that i stated above.
then in terminal one would type
"./bzfs -dd -conf /users/myname/myconf.conf"
the two -dd stand for debuggin level you can up that to -dddd to get a read out of all errors etc
that will open you config file along with you map, and if you have completed the file correctly will run a server (you may have to open a port on your router/firewall if you have one, google it if it doesnt work).
Now your server should be running, you can look at commands and server variables of of the bzflag.org homepage under the wiki.

Now to talk about bzadmin
to run bzadmin one would enter
"./bzadmin"
then it will ask you for username, password, then the server address and port number, once in you can do anything as an observer except observe the game, if you are an admin, you can chat with other players or change variables, its just a simple program

Now to talk about bzflag
to run bzflag you may click on the icon of course or from terminal type
"./bzflag"
then it will open bzflag and you can access any server etc.

Now for all three applications there is a help part which you can access, and it will tell you all the commands for each one
for bzadmin you would enter in terminal
"./bzadmin -help"
for bzfs
"./bzfs -help"
and for bzflag
"./bzflag -help"

to run a certain amount of very stupid bots that cant jump and are just like fodder you may enter
"./bzflag -solo #"

Hope that helps, any questions email me at sir.monkey.pants.ster@gmail.com
i also admin on Planet Mofo so check there
~Sir Pants~
the # being amount of bots