kaillerasrv-ppro.exe is a binary compiled for Pentium Pro and above CPUs (just about any modern system that isn't a Pentium/K6 family system or older, which means anything that isn't pretty old, probably anything >=600MHz). kaillerasrv.exe is a binary compiled for Pentium and above, which should run on even those older systems, for those who care.
As far as setting up a server.. you'll pretty much need most of your ports >=1000 open for bidirectional traffic (when a client sends a request on the main server port, the server asks the OS for a port and then sends the port # received to the client, which the client connects to), as well as whatever port you select for the server in the cfg file (defaults to 27888).
In my opinion, most of the options in the cfg file are fairly self-explanatory.
