Krug is a piece written by Bill Connor, of which MetaBrainz has three possibilities.
One has the same birth year (1949), but a different spelling of the last name, and the other two could be, or it could be someone else.
What should I do? Add a new Bill Connor? Guess?
When in doubt, it’s better to create a new artist. Simply because it is easier to merge two artists when more information becomes available than it is to untangle an artist that should be split. Just be sure to write a short but informative disambiguation comment (like “composer of Krug”) and maybe an annotation to explain why you added a new artist and that it may need to be merged in the future.
And if you ever have a spare weekend, and enjoy detective work, you can go through all the other artists and try to untangle all the 'Bill Connor’s with disambiguations and identifying info etc 
In this specific case: Bill Connor - MusicBrainz composed Time Dances, a search took me to http://archive.is/Hpobb#selection-243.5-243.11 which claims he’s born 1949 and “he has written much chamber music”. So I think it’s safe to use him here (I’ll add extra info to his page now).
It’s perfectly possible that the production music composer is the same person, but who knows, since it’s production music.