Multibox Setup - Am i dumb?

Hi everyone.

I cant bring Multibox to work. I tried synergy but i cant play with this
spinning-around-mouse-movement-feature, also the workaround doesnt
work for me. I tried multiplicity but from time to time it locks my
gameplay window, so i have to end up ALT-F4 to get out of the game.

I tried multibox, nut i cant get it to work. Here is what i do:

My Setup:

PC Name: PC (Server+Client)
Laptop Name: PC-G2 (Client)

EDIT: Both are Vista PCs

I start up the server. I change it to 1,2. i strat up the client on PC. its reads: client connected to PC: 192.168.52.5
so i can select pc for the first "tab".
I start up the client on my laptop, i fill in the servername: PC and hit
enter, the server reads: client connceted to PC: 192.168.52.6

If i use the pulldown menues its reads from top to down:

empty / PC / PC

on both pulldown menus. i tried every combo, but i cant get thos program to work.

is there anybody who can help me please?

Thanks in advance.

Hertome

P.S. English is not my native language, sorry for some misspellings.
just in case

P.P.S. I started Mutlibox on my jobs PC and it shows me lcalhost as the first option in pulldown menu?