I am trying to determine how, or even if it's possible, to configure Multiplicity to run on one network and connect to two other computers that are behind a juniper firewall.

The scenario:

We have a Radiation Therapy System which utilizes 3 computer setup. 
The primary computer is located on network 128.xxx.xxx.xxx
The two secondary computers are located behind a juniper firewall that is on 172.xxx.xxx.xxx & 172.xxx.xxx.xxx

To make maters worse, two of the computers must run Windows XP while the 3rd computer runs Windows 7. Multiplicity 1.21 is currently installed on the two Windows XP computers, as they are the original system. We needed to add a 3rd computer to interface software between those two and a server, which runs on a Windows 7 workstation.

I'm not even sure this will be possible, but currently we are using a KVM switch to go back and forth and when you have to do this 20-30 times in a 10 minute time period it becomes a nightmare.

We purchased a new license for the Windows 7 box, and it would recognize them but wouldn't actually "connect". The computers are "greyed" out. 

Any thoughts on this?