I'm made some tests but it doesn't seem a reason to make the game block on my end
I kind of think that this is due to having Gura in your party
If that's the case, try removing her from the party before going into the last stage you visited
If that doesn't work or is not possible you can send me your saved data to take a better look at what could be the reason
(your saved files are under the directory www/save/fileXX.rpgsave if playing on windows (if playing on mac I wouldn't be able to take a look though). You can send it on the discord channel for the game here:
https://discord.gg/tsrjqPpK