The image works with the BBB. But you have to run the build.sh osbo first.
But it’s better to work with Ubuntu and install OpenSprinkler. On the image is an old software and you have to understand date it. The update is like a reinstall.
You find a discrition for update/install in the docu.
Sounds like you’re trying to use a raspberry pi image on a BBB? I’ve not tried that myself but I have installed the actual BBB image from http://www.raysfiles.com/osbo/osbo2.zip It works. It has the old software though, so as David mentioned you’ll need to update it. I’ve also installed the latest BBB Ubuntu image following the directions here http://elinux.org/BeagleBoardUbuntu I then had to install the build-essentials package before I could install the latest version of the OpenSprinkler unified firmware. However that also worked.