Sidecar files with Digikam

Hello forum.
I am new to FRV.  I must admit that the name of the program is well deserved.  Impressing!!.
 
I am an amateur ornithologist who never leave home without the camera.  I manage my picture library with Digikam and process my pictures with DXO Photo Lab.  If I have lots of pictures to process I start with FRV.  But more and more I use it even more as I discover FRV's features.
 
I found how to rename the sidecars in FRV using XXXXX.ext.xmp which is a heck of a great feature and matches Digikam naming "standard".  But I seem to have some issues though.  When I apply a rating in Digikam it is not reflected in FRV and if I apply a rating in. FRV, it is not apply to Digikam.  The rating appears in the xmp file though.  I place here some xmp output of relevant portion of the picture rating for comparison purposes.  The rating is different as of course I am using two different pictures to be able to see the format.
 
Here is relevant portion of an xmp file as written by Digikam
 
<?xpacket begin="" id="W5M0MpCehiHzreSzNTczkc9d"?>
<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="XMP Core 4.4.0-Exiv2">
 <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
  <rdf:Description rdf:about=""
    xmlns:xmp="http://ns.adobe.com/xap/1.0/"
    xmlns:photoshop="http://ns.adobe.com/photoshop/1.0/"
    xmlns:libraw="http://ns.libraw.com/librawxmp/1.0/"
    xmlns:crs="http://ns.adobe.com/camera-raw-settings/1.0/"
    xmlns:acdsee="http://ns.acdsee.com/iptc/1.0/"
    xmlns:MicrosoftPhoto="http://ns.microsoft.com/photo/1.0/"
    xmlns:tiff="http://ns.adobe.com/tiff/1.0/"
    xmlns:exif="http://ns.adobe.com/exif/1.0/"
   xmp:MetadataDate="2024-05-05T11:52:40-04:00"
   xmp:ModifyDate="2024-05-05T10:48:15.00"
   xmp:Rating="3"
   xmp:CreateDate="2024-05-05T10:48:15.00"
   photoshop:SidecarForExtension="CR2"
   photoshop:DateCreated="2024-05-05T10:48:15.00"
   photoshop:Urgency="4"
   libraw:MetaDataDate="2024-05-05T11:35:13-04:00"
   libraw:Version="20007"
   libraw:FRVS="BLE:1/0/0.75/-0.28;AE:0/1/1.00/2/6400;WB:0/0/0;CNTR:4/0;FBW:0;CM:1/0/0;XMP:0/1/2/1"
   libraw:Contrast="9"
 
And a complete file as written by FRV
 
<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="XMP Core 5.6.0">
   <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
      <rdf:Description rdf:about=""
            xmlns:xmp="http://ns.adobe.com/xap/1.0/"
            xmlns:photoshop="http://ns.adobe.com/photoshop/1.0/"
            xmlns:libraw="http://ns.libraw.com/librawxmp/1.0/"
            xmlns:crs="http://ns.adobe.com/camera-raw-settings/1.0/">
         <xmp:Rating>5</xmp:Rating>
         <xmp:MetadataDate>2024-05-05T11:52:48-04:00</xmp:MetadataDate>
         <photoshop:SidecarForExtension>CR2</photoshop:SidecarForExtension>
         <libraw:MetaDataDate>2024-05-05T11:35:17-04:00</libraw:MetaDataDate>
         <libraw:Version>20007</libraw:Version>
         <libraw:FRVS>BLE:1/0/0.75/-0.28;AE:0/1/1.00/2/6400;WB:0/0/0;CNTR:4/0;FBW:0;CM:1/0/0;XMP:0/1/2/1</libraw:FRVS>
         <libraw:Contrast>9</libraw:Contrast>
         <libraw:Exposure>0.356144</libraw:Exposure>
         <crs:ProcessVersion>6.700000</crs:ProcessVersion>
         <crs:Exposure2012>0.630000</crs:Exposure2012>
         <crs:Contrast2012>0</crs:Contrast2012>
         <crs:Whites2012>0</crs:Whites2012>
         <crs:Blacks2012>0</crs:Blacks2012>
      </rdf:Description>
   </rdf:RDF>
</x:xmpmeta>

Some pointer would be appreciated so I can streamline my process and spend more time watching the birds.
Regards.