'New-CMOperatingSystemInstaller' powershell cmdlet not working correctly

After using the 'New-CMOperatingSystemInstaller' powershell cmdlet for importing a operating system installer into SCCM 2012 the option 'Distribute content' is grayed out for those installers.

Microsoft have confirmed that the properties are not set properly using powershell and have logged an internal issue on this and are looking at fixing this in a future release. 

The recommendation in the meantime would be to use the UI, or to use WMI to create or modify the properties of that object.