Oh, no. Did you play the game before? It might have had some old data saved. I have pushed an update that should clear that out. Let me know if this fixes things! If not it'd be great to get a copy / screenshot of the red text 🙏
Oddly, I hadn't, but also oddly, I'm no longer getting that error, so whatever you pushed seems to have fixed it. (If it comes back I'll give a more detailed description!)
EDIT: Wait, I take that back! I hadn't recognized the name, but I did in fact play it ages ago, so there was almost certainly some sort of old (I guess pre-druid?) save information in there. Well, that totally explains that.