I'm hoping that someone can answer this question off the cuff. Please don't do any research; that's my job.
When I fetch an image via the API from a remote wiki using ForeignAPIRepo, the thumbnails end up with a local URL How do get it to use the remote thumbnail URL? E.g. as on this page: http://ersch.wikimedia.org/index.php/File:171296_494394106964_721816964_6660...
The original comes out of wikipedia/commons, but the thumbs are coming out of images/swift/thumb, which is not to my liking. Instead, I want the images to come out of wikipedia/commons/thumb. Alas, this says nothing about it: http://www.mediawiki.org/wiki/Manual:$wgForeignFileRepos