I'll try to reproduce this and look into tightening the error handling. A 404 error should imply that the magazine is not available at the remote. Are those magazines available at the target instance? Agree that those should at least be added to the log--perhaps should add a third category for "Unavailable." Remember that it will also navigate you to the magazines list at the end for visual confirmation.
When you said community subscription, were you referring to something in particular, or just using this term generically to refer to magazines?