Ghost 12 - adding remote computers

Hi, i’m using  Norton Ghost 12,( 12.0.0. 20352) and I’m trying to add my laptop
to “add computers” tab. I’m using network magic at the moment to
establish a connection between my desktop, and my laptop, so that i
can share folders, a printer, and the internet via a router. All is
well with network magic, and it’s simple to use, when i’m sharing
files etc. Now comes the problem.
I’ve installed ghost 12 on my desktop, and I want to ghost the image
of laptop, place the image in a folder on the desktop PC, in case the
laptop buggers up. That way, I can transfer back the image to the
laptop at a later date… However at the tab where you ad computers,
the wizzard asks for the ip address of the remote computer. So i type
that in, and then click ok. next, a window asks you to add network
credentials, and it asks you to type in the username and password. So,
i type in, the computer name acer-47253a5cc0\Graham but where’s the
password? i’ve tried all the passwords I know,  the WEP key? the logon password? admin password?  but i’m still no
further!
BTW, the desktop, and laptop is a member of a workgroup- will that
make a difference? if so, how do you change to a domain? I’m running
XP Pro service pack 3 on the desktop, and Vista Home premium on my
laptop. Help!!
Lou