Thank you so much for trying out the update!
The highscore and oil issues definitely suck, I'll get to fixing those straight away. And the ore density is a very experimental feature, so any feedback for tuning it is very welcome!
Also, there is actually a cancel placement button! A bit of text shows up in the upper left corner to explain it whenever you are placing something. But if you ended up missing it, I should probably make it stand out more!
Lastly, and funnily enough, indication for destructable terrain and some sort of drill boost for sticky situations, are both features I was considering for the next update! So I'll definitely start work on them when I can.