Installation and usage of ACR 5.2, for Mac, was completed w/o problem. However, new (to me at least) was the inclusion of what appears as a camera profiles 'package'. Sorry, don't recall the extension. Where should this file reside (on a Mac) for use by ACR?
Just double click it and it will install in the correct spot. The correct spot is /Library/Application Support/Adobe/CameraRaw/CameraProfiles but there is no reason that you would ever have to know that.
On Windows, it's C:\Documents and Settings\All Users\Application Data\Adobe\CameraRaw\CameraProfiles.
If you create your own camera profiles, they are stored in C:\Documents and Settings\username\Application Data\Adobe\CameraRaw, in the CameraProfiles subdirectory. I back up this folder, together with all the other settings subdirectories there, in case everything goes belly-up.