I'm starting this thread just in case it may help someone else in the future, and it's probably obvious to people who use unix/Linux all the time, but I'm a web designer and rarely spend any time in terminal.
Some quick background, I plan to get a Beaglebone Black and run Blackbox on it. But since the BBB is currently not in stock anywhere, I'm gonna get it running on my iMac (running OSX Mavericks, 10.9.3) and start making some improvements to the Blackbox UI.
First thing I did was read the great Installation page
https://code.google.com/p/theblackboxproject/wiki/Installation on the blackbox project page, and was directed to get newmodbus from RossW, which you can download here:
http://support.rossw.net/midnite/Once you've got it installed, you'll need to run Terminal and change the permissions to allow you to execute the file:
chmod u+x newmodbus-OSX
From there, it should work as directed in the instructions:
./newmodbus-OSX 192.168.1.150 4101-4111
Now we should be able to get blackbox installed and running! I'll post any more tips I come across as I get this working on my iMac.