Using the mod works sometimes but most of the time it either generates areas that dont have any materials in them, or generates mining that does not have all the materials in it.
Tried to do it with various patches and settings but it just has issues with weird forms of patches ( and these are the patches you want this tool for )

Tried it on new haven map. The patches of titanium ore and it just cannot effectively mine them. It either ignores obvious patches ( like 1 layer into the ground ) skips areas that are just next to what it is digging out.

Dont think it is tied to the save, what i did is just go to the top right island on new haven, place a tower select an area with titanium in it and let it set the mining desingations.

So, I tested on this patch and I found it's working fine for me as long as I'm setting the filter to Titanium Ore. This patch seems to be difficult in the sense that it's shallow, poor, and mixed in with sand and quartz. So, leaving it on Auto, it will pick up the sand and the quartz, which messes up the designation. Let me know if this helps.