Many thanks for sending me the error - I tried to email you by reply, but it was just bouncing back for some reason.
Looking at the error, the game is trying to upload the next conversation for Switch but, because this is the demo, the next one is unavailable.
I've fixed it now and am rebuilding the demo - it will be about 10 hours before the fixed copy is available to play, but I thought I had better let you know in case you were looking forward to getting another chat with Switch once the error was fixed - sorry. >_<
Thanks for playing ^_^