I've got the same problem as you.
I want to edit the CATALOGNUMBER in MP3Tag and be able to see it on Traktor as CATALOG NO
i'm on a mac version of MP3 tag
i created a new field named CATALOGNUMBER, i may insert it the %catalogid% but i never see it on traktor.
I also see that when you edit the value in traktor, i can't see the result on mp3tag. When looking at extended tag, nothing match
Then how do you solve on your way ??