Dude, check out my mining script. I scan just like that through all of the layers of each spot in a grid around the toon looking for minable/sandable (and soon lumberjackable) tiles (thanks to OMG for the original versions of those subs). That's why it's always worked in Ter Mur, it doesn't look a specific tile information, it checks them ALL and tracks the ones that give up resources.
I'll be upping my tmapper helper version 1 today too, I used a modified version of the same subs to scan for the treasure map dig location around the toon.
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