Well, here's how I do it. My A4000 and my WinXP machine are both on a LAN and on the net at the same time. I use a router to connect to the internet, which also connects all internal computers. The nice thing about the router is that it provides firewall protection for both. Once you set this up it's pretty simple and you don't even need MiamiDX, I just use the normal Miami.
I just installed Samba, but I'm not sure how to mount remote samba drives yet.....
- Mike