I used to get connection failures between explore event missions – this was something that happened semi-regularily, and at exactly between missions, so I don’t think it was caused by a bug, not real network issue. It was a small annoyance, but now it has escalated, usually forcing rebooting the game when it appears. Now I’ve been getting it when trying to go to the event, not just between missions.
Another new bug requiring a reboot is if you get to the last boss in Fens challenge with a single character (in my case Saarvin – and this has happened twice), the game may get stuck. I believe it happens only when the character is killed on the second of the dragon’s attacks.