i enjoyed it a lot. i'm sick of these kinds of short loops with upgrade trees so that i finished the demo says a lot :D the mining is very satisfying, This is on my wishlist.
I may have locked myself out of some upgrades by building the smithy before i purchased all the copper upgrades, and later on it seemed copper wasn't even present on maps (or am i misremembering?). i have no clue what caused the demo to end