So, I just installed the latest update (4.6.9995), and the Agony Column is still causing a reboot, although it seems to be happening faster? The other book that I had purchased from kobo is working correctly, though, so I'm just going to move along for now. Would love to see the Agony Column book eventually, since the bit that I read inside Calibre sounded interesting, but that is lower priority for me currently.