MC can read and write certain XMP tags. Specifically, MC reads tags that XMP tags that correspond to IPTC tags, which are part of the XMP "photoshop" and "dc" schemas, but does not include a ratings field.
We certainly would like to include other commonly used XMP tags. Better yet would be the ability to customize mappings between XMP tags and MC fields. But that would be for the future.
What is the ratings tag from Adobe Bridge named? What are the other fields you use? Actually, it would be helpful to get a copy of the format tags listing, so I can see what schemas the tags are under.
JimN