by James McLean.
Thanks David, that's the process I'm following but Behat never opens a Firefox window when Selenium is running, which is why I tried to start the Firefox session manually from the Selenium Web interface.
I don't see any errors in the Behat window regarding connecting to Selenium when running with --verbose, and I don't see any errors in the Selenium window about starting a session when Behat is running. I'll see if I can find the Selenium log file and have a look there.
I also received a firewall popup when starting Selenium which I allowed, that didn't seem to help.