Okay, but that's still not what you've been asked for by multiple people and this is frustrating to the point that I'm not sure if I want to pay for the full game anymore.
For the demo, allow going to the mine as many times as we want but prevent the player from going past a certain level. So, we can mine down to level 5, for example, and then we can keep delving to forest or mine level 5 as much as we want, but limit level 6+ to the paid version.