Can't use stone grinders.
 

If I try to put minerals into the stone grinders in the houses beside each of the mines, I'm told to do the mining task. Attempting to actually do the mining task doesn't resolve the problem.

Recently I had to redo the shovel and lumber axe tasks just so I could build fireworks and an icebox (two different towns, two different crafting tables..same problem).

Sounds like a similar bug.

If the mining task is done it works actually.

I added something so you are able to use them if you already did the "old" tasks.

Yeah, but when I went to go do the task, the NPCs told me I'd already done it and wouldn't let me do it.

Tha's some conflict with the old and new tasks - Can probably add some npc you can talk to, that you are able to do the tasks again.