yeah the problem is when u connect to GN even though the servers etc are on different machines they all use the same global accounts database. Thats where the problem is.
I think the solution lies with finding a way to link the 2 computers together, and have them function as one server...players who create accounts for the first server will have the same details for torozor, and vice versa, and both servers should be able to function independantly of each other.
however this is only an idea, and i have no idea how it can be pulled off
EDIT: after looking at your edit that sounds like its should be possible. I see no reason why that shouldnt work as long as u configure all the files etc correctly. Just make sure u dont end up using ports that may be important or something.