Comment 21 for bug 407991

I don't know if there is something wrong with VirtualBox or something but you've got odd problems.

You torrent file works fine here... I see a single zip file in it, size: 126.1 MB.

Regarding the seeding of existing torrent files, this is pretty easy (and the same in all clients as far as I know). Simply add the torrent to qBittorrent and select the destination folder where there files are already present. qBittorrent will check the files and then seed them.