Interesting. I came unto this discussion because I had a research article on iCloud in pdf that refused to open. It had the download arrow with the cloud as you stated. Peter is right. I could not open the article on my Mac, but went unto iCloud via Safari and it was there. So I downloaded it, then replaced the same copy on my Mac on the iCloud tab in finder and now there is a local copy on my Mac.
So like Peter said, it seems this means the document with the downward arrow is a copy in the cloud that does not have a local copy on your Mac. When I tried to delete it from the iCloud finder on the Mac, I got the warning that it will be permanently deleted and there's no way to recover it. So thanks Peter. Now I know what that means and when I see such files, will make sure I download them so I have a local copy for backup.
Borddude i agree about the lack of force syncing. This is particularly true when you consider that not everyone has good internet access so synching can go wrong at anytime which i've experienced. It's always good to have a way to force it to sync so one knows the task is done. Hope it came right with you thou.
Cheers!