thanks for the report, i gotta investigate what's going on. That message should only appear when I've updated the save format, and this isn't obviously the case here. The credits reset isn't to blame either, the game only saves when you touch the Salavia flower. I suspect the data is actually fine. If you can, it would help debugging if you sended the save file to borbware (at) gmail, it's a gibberish named file located in appdata/roaming/com.nesbox.tic/TIC-80/.local
Anyway, great that you liked the demo! Thank you for playing! :]