.XMP in CameraRaw/LocalCorrections not appearing in Camera RAW menu

Hello,

I am having repeated problems with some of the .XMP files I copy to the CameraRAW LocalCorrections folder - I copy them to the folder but they do not appear in the Presets drop-down menu in CameraRAW (even though they appear in the index.dat file).

Let me be more specific:

I have a set of CameraRAW brushes which I'll call "CP".  When the CP set is installed, no other 3rd-party brushes copied to the LocalCorrections folder will display (although they are in the directory and are listed in the updated index.dat file).  If I delete the CP set and install other brushes, then (so far) the other brushes show up in the CameraRAW and can be used.  However, if I reinstall the CP brush set, they seem to override the Presets drop-down menu and even though the older brushes are still in the index.dat file, they do not display in the Presets drop-down menu and I am restricted to only the CP brush set.

I am using Photoshop 24.4.0 and CameraRAW 15.3.1.