Thanks for digging out this information. I am concerned that there isn’t as much focus on the crypto the protects the portion of the ballot that can be tallied. In order to be useful, the human readable information that is discarded at time of voting still has to be associated with the ballot even if heavily encrypted. There are hints that a shared secret based keying system is used but to say it is totally unbreakable or absolutely secure is misleading. I just wish as much information was published about the crypto as the clever takeaway receipt.