I haven't done this, but have you considered an alternative approach - disabling the firewall post-install via netsh (so it could be scripted?) ...

That's the problem. Exchange uses a range of around 2000 ports - some of which get used for other things as well. Microsoft pretty much told me "Don't do it that way. Shut off the firewall when ...

1. Disable Firewall and Antivirus Windows Firewall or third-party antivirus software monitors traffic to prevent unauthorized ...