Salem

So I have a MIne, made a Mining Entrance, did the Fire, the wall has cracks...

Went to Adv > Mining,,, click on the crack areas with a pickaxe .. nothing is happening?

What am I doing wrong..

Have you clicked on the floor tile where the cracked wall is "overtop" of?

The hitbox registration goes off the floor, not the actual wall. Hopefully they'll change this at some point, but that's the way it is.

OHHHHHHH... there it goes ..

ANother question - The Ore Bounders that you take out - do they have risk of Decay / Despawning?

Far as I know, they are treated like logs/boulders. Immune to all forms of decay.