This note is for when the user tries to write to the SD card via the installer on MacOSX but on writing the installer is seen to hang and has to be force quit.
The installer uses, what Apple calls, a "helper process" in order to be able to write the contents of the image to an SD card. This help process is run with root privileges.
In order to run with root privileges the helper process must be installed and run by the Installer application itself through the appropriate MacOSX security API. This in turn uses Apple's launchd system to installer the helper process.
MacOSX in turn requires permission from the user to do this and so in turn asks for the login of an account with admin privileges.
However it maybe seen that this installation process does not take place properly. So the application locks up because it thinks the installation process has happened (because success is reported by OSX) so when it invokes the helper process it hangs indefinitely.
Resolution. The helper process must be uninstalled manually from the Terminal using the following commands.
sudo launchctl unload /Library/LaunchDaemons/uk.co.blackomega.hifiBerryInstallerHelper.plist
sudo rm /Library/LaunchDaemons/uk.co.blackomega.hifiBerryInstallerHelper.plist
sudo rm /Library/PrivilegedHelperTools/uk.co.blackomega.hifiBerryInstallerHelper