Read there ...
Move "Featuring" from Artist to Title
Applying a proper filter expression can help to reduce the view and the work to the files in question.
If you follow the advices, then you should have success.
What tag-type do you actually read from the files?
What tag-type do you actually write to the files?
Make sure, that you read and write to the same tag-type.
DD.20140708.0656.CEST