I would just use "gold" to mean copper. We can't have EVERY color in the world, so sometimes you have to double-up. If you're seeing errors of any kind, please report them immediately! If you're getting an error, please cut 'n paste it--it should be all I need. Otherwise I'll need to know the steps you took, the browser you're using, the music you had playing, etc.
As for white backgrounds, that's only required for the "reference" shot (used for browsing, mainly). You can use any kind of background you like for the gallery shots, though we do still ask that it be in focus, brightly-lit, and all that other good stuff. I know that's not very clear from reading the guidelines--I plan to rewrite them yet again to clear that up.