The new installer turns off the Windows Firewall after the installer closes. If Windows Firewall users don't restart their computer immediately after, does this mean they are left unprotected until CPF runs at startup?
Actually Windows firewall users are fairly unprotected to begin with,

. Seriously, IF by default , Windows firewall will be shut down (mine doesn't ) but it will still monitor LAN (although protecton here is hard to say) and would be a good idea to uncheck that after another is installed. Also, if you mean the new CPF installer, you are promted to restart the computer, and a technical average of 16 minutes before you are considered in true danger without a firewall running. If ever prompted to restart for these reasons, unless you are in very important matters (which I don't know why someone would install anything anyway then) but ALWAYS try to restart as soon as possible. I hope I don't get too technical about the biggest solution and I will list the steps below to solve this....
1.) turn firewall back on until ready to reboot, then shut it down when you do.

Hope this helps,
Cheers,
Paul
P.S. one of the only ones I know that do this is ZA.