We're sorry that you're still having the problems. I have personally tested the update (downloaded from the Try Now link), and it does correct the problem with the security key errors. However, depending upon where you live, it can take several hours (even overnight) for the updated version to propagate to all of the cloud servers. You might want to give it some more time and try the download again.

All of our games are "unsigned," and Microsoft and 3rd party security software will issue various warnings about software that is not digitally signed. We have personally checked all of our uploads, and they are safe to download.