Hi,
I've rebuild the game using Ren'Py 8 / Python 3. This new version includes several hardware optimizations and fixed a bug on level up (Mind attribute not resetting).
The downside is that it doesn't work anymore on 16-bit versions, so for now I put this new build in a new beta branch that you can access by going into the game properties and choosing "beta" in the beta builds.
Once I'm sure this new version doesn't have any bug, will make it the default and keep the old ones for users who are still on 16-bit systems.
Note that due to the new MacOS restrictions the game might not work anymore in future on Mac.