System Link in Cubase SX2

[cadebusy]

Hi ppl, I am new to this forum so apologies if this one has been aired before.
I am trying to setup System Link using two computers ...one with Cubase SX2 the other has V-stack.
Echo Gina soundcards in each machine...one is 24 bit ..the other 20 bit.
I think that I have tried to do all the connections as per manual, but no luck.
Steinberg help UK dont seem to know how to set it up and Echo Audio said that they could get it working but only for a short time.
Has anyone managed to get System Link working and if so, could I have an 'idiot language' tutorial.
Please!!!.