In this update, there were some changes to how you receive the Sword of light, you no longer receive the sword at the Mishaela battle, but at a chest upon arriving at the next town. You can't miss it, as it's right next to where you spawn. Reason for this was the dialogue branch for the npc that was meant to give it to you if you didn't receive it during the Mishaela battle, would be finnicky and sometimes not use the correct path.
Chapter 6's dragonia's map and movement scripts have been updated to keep players from leaving Dragonia until they complete all the scenes (aka: the Kane/darksol clash and picking up the item left behind)
When you return to Rudo, you will NOT find Krin there. Talk to the two npcs at the gate and they will explain.
I have tested this fix a few times and so far I haven't had any issues with this current workaround. Let me know if you run into any problems with Chapter 6.