Two major changes have been made to the ATS Mining Process.
The minerals your break lose from the vein are spawned inside the vein, which means you need to deplete (break) the vein to get to the minerals.
Note: For Automining to work, you need to first toggle it on in your Crafting Menu.
If you click on the vein once, not Bash, your character will automatically start mining the vein until it's either depleted or your pickaxe breaks (once per every 5 seconds).
If you move away 5 meters or more from the vein, Automining will be cancelled.
Also note that if you are too unskilled to mine the vein in question, automining will not start.
Should you wish to attempt to break lose one single mineral while Automining is activated, simply Bash the vein once.