Just a tip (or learn from my mistakes):Do not attempt to install CSA remotely via RDP (Terminal Services). The install interupts the network stack, disconnecting the RDP client. The agent kit installer session ends up in la-la land.
Don't balk on internal network segmentation. Its all doable, and it will pay off. With regard to the Exchange issue, note that RPC communications on Windows servers can be configured to use restricted port ranges via policy. Restricting the RPC ...